I'm not sure I can do this without causing Fionwe and Darius to have acute chest pain, but I'll try.
We now have the strength list of the channelers and we know that it stretches from 1 to 66 for the ladies. We also know that there are six male levels on top of these, bringing the levels of strength to 72. However, considering RJ said that the strongest man and woman are basically equal in effectivity, the list remains at 66 levels, with the high strength males merging into levels 1-3. These 66 levels then represent effective strength. If we then make OP strength from 1 to 100, and fit 66 levels into this, then we see that there is a little more than 1.5 effective strength between each level.
Character effective strengths are therefore: ((66 - character level + 1) x 1.5)
100 - Ishamael, Rand, Rahvin, Lanfear, Semirhage, Alivia
98.5 - Demandred, Aginor, Sammael, Sharina, Talaan, Graendal, Mesaana, Cyndane, Logain.
97 - Asmodean, Balthamel, Graendal, Nynaeve
95.5 - Moghedien, Someryn, Be'lal
88.5 - Egwene, Elayne
87 - Cadsuane
84 - Aviendha
81 - Moiraine, Elaida, Siuan, Romanda, Lelaine
72 - Berenicia (minimum level to effectively Travel)
48 - Siuan (post-stilling)
33 - Daigian
15 - Sorilea (and minimum strength to lift a feather with Air)
1.5 - Moiraine (post Finns)
The first question is what is average female strength? Well we don't know, we don't have enough numbers or samples, and the Aes Sedai are skewed. We know that Aes Sedai strength runs from 33 to 81 (excluding Cadsuane). We also know from Elayne that not many women are as strong as Sheriam or Kiruna (79.5). We therefore have to assume that most women are weaker than 79.5. Galina also tells us that none of the Shaido are truly weak in the Power, with one of their weakest sitting around 60 (Micara). Considering you need a strength of 72 to travel effectively, this explains why most women cannot travel. The weakest AS in the Tower above Daigian have strengths of approximately 40. Daigian is an extreme outlier due to her circumstances. Egwene tells us that most of the 1,000 women they found will never be Accepted and that most AS cannot Travel. Egwene also tells us that some of the Wise Ones are as weak as Sorilea and others are as strong as Amys. If you therefore take female strength to generally range from level 57 to 13, then the median female strength level is 35 (Siuan post stilling... strength 48 ). For practicality then we can use 50 as the average female strength. This is a perfect bell curve distribution then.
So can this be applied anywhere in the series? Let us look at some of the quotes that have been presented to us in the past and see if they stand up to scrutiny.
LoC (The Mirror of Mists) - Seven. Lews Therin groaned. I cannot handle seven, not at once.
Let us therefore consider 50 x 7 to be something that Lews Therin cannot stand against = 350.
LOC (The Taking) - That shield made his eyes bulge, it was impossible. No three women could block him from the Source once he had taken hold of saidin, not unless they were as strong as Semirhage or Mesanna … Rand felt the blood drain from his face. Four sets of eyes in four ageless faces examined him.
3x Semirhage/Mesaana = 300. We also know that Lanfear, Graendal and Rahvin wanted to link to shield him , and that number approaches and agrees with this statement (strength 297). Rand gets upset when he sees 4 women, so if we take 300 among 4 channelers we are looking at an average strength of 75 (level 17), or roughly four women of Alanna or Verin's strength to completely smother him. These stats actually work quite well because they show that it takes 3x Forsaken to shield Rand, or 4x level 17 or greater.
This is why Asmodean says that 13 women who can barely channel can shield most men... 13x Sorilea (15) = 195. If you need a factor of 3 to conclusively shield then anyone above 65 strength can potentially defend themselves against these circles. We have actually seen Rand deflect a weave aimed by a full circle. However, Asmodean says that 13 of the weakest in the Tower could shield any man. If we take the weakest women above Daigian, about level 40 (strength 40) then a full circle will have a strength of 520, well above LTT's abilities.
We know that Cyndane has a strength of about 98.5. Elayne's angreal was described as weak and made her twice as strong as Nynaeve. The multiplier was thus 2.2. We know that Nynaeve's angreal was of significant benefit and never considered to be weak. Therefore when Alivia fought Cyndane she had a strength of at least 220, and narrowly escaped with her life.
It seems therefore that skilled and knowledgeable channelers only become smothered or unable to win unaided when they are facing more than 300% of their strength. Therefore when Egwene says that she can potentially overwhelm 5 AS if she is quick, this is not nonsense, as she can handle women up to 265 in combined strength before being overwhelmed by strength alone, and therefore an average strength of 53 between five sisters. Remember a strength of 64 is rare in AS, so her captors really could have been at this level or weaker. If she can catch them before they grab the Source she could win.
I'm ignoring the loss of strength in a circle, but also the increase in precision with linking, so let's hope it balances out.
Regarding the Cleansing, it is difficult to find any sort of evidence because we don't know the strength of the various men, and many of the women used angreal. But let's try anyway...
Graendal faced Verin, Kumira and Shalon. We don't know how strong Shalon is, but Verin implied that she was stronger than her in the Power, so at least level 16. The circle's minimum strength was therefore 216. This is below the threshold required to shield Graendal conclusively (291), although Verin had an angreal and so did Graendal.
Demandred faced Sarene, Corele and Flinn. Flinn has a strength level of at least 18 because he can Travel, and the two women have the same strengths. Combined strength of the circle : 220, and with the huge advantage of mixed flows.
Moving on...
ACoS (A Pair of Silverpike) - “It had to be one of the Forsaken. Do you really think Faolain and Theodrin together could have stopped him? I’m not sure I could have, even linked with Romanda and Lelaine.”
Combined strength : 250. This is once again below the 300% smother factor for all of the Forsaken, but enough to be a very difficult circle to confront. It's likely that Cyndane faced this much power when she fought Alivia.
TPoD (A Quiet Place) - The white-haired sisters were linked … There was no way to tell which led the small circle and held the shield on the Darkfriend, but not even one of the Forsaken could have broken it.
Combined strength : 132 - considering a weaker woman can hold a shield on you, this circle can hold any woman by a long shot. We have seen this fact duplicated when they held Semirhage, though they used three women due to caution. We have also seen two women hold Nynaeve. For some reason it takes many more women to hold a male, but this is OP difference that exists because it does. While a weaker woman can hold another woman, it seems like a male can even break free from a greater strength. It was suggested that Logain might have broken free had only five sisters been holding him, so the shielding power required to hold men may be over 150% of the male's strength.
In TSR Amys releases Egwene from her shield and says that she cannot hold her for much longer. Amys' minimum strength is 76 and although Egwene was not quite at 88 at this point, it seems like this gap teeters on the amount of strength difference required to break a shield. Galina (strength 79.5) said she could easily have broken Micara's shield (strength 60). Therefore it is likely that you need to be 12 to 20% stronger than someone to break their shield, but probably closer to 12% given these two quotes... 15%?
What's strange, though, is that according to these calculations Siuan has a post-healing strength of 48 and a pre-stilling strength of 81. However in LOC she asks Nynaeve to please try and Heal her to at least two-thirds of her previous strength, or even half. This implies that Siuan having a strength of 48 is not correct. Her strength should be less than 40 and she should be at level 40 or below, and not at level 35.
So what are some of the key points of this text? From the definitive list of the strengths we can possibly say...
That you need to be 3x stronger than a channeler for them to have no chance. Below this a skilled channeler can still duel you. We have seen several Forsaken do this.
That a channeler can fight up to 3x their own strength using skill and ability. This is prima facie evidence of the true value of skill with the Power.
That many of the texts in the books make sense and align with this strength list.
That a woman needs to be about 15% stronger than another woman to break her shield.
That two women can hold any woman so long as they exceed 100 in combined strength.
That it requires many more for men, for no reason. Much like a bridge of Air between the two sexes.
Average female strength may be around 50 out of 100.
I'm not saying that any of this is fact, but maybe it's close to the real numbers. This is all very rough, and even if we knew everything about the OP it seems like everyone has Talents, strengths and weaknesses with flows, angreal or sa'angreal or friends to link with. It's a giant mishmash of data, and perhaps this provides us with some rough "rules" regarding the Power.
The theory is designed to have predictive power... if I was Egwene I could work out how many women it would take to overwhelm me, or how many I could overwhelm... much like she did. Or maybe how many friends I should get if I want to shield Demandred. You can probably roughly work it out... Lanfear and friends certainly did and LTT had a rough guide to protect himself but when it comes down to it you'll have to see how it all turns out. You never know who is strong and weak in what.
Fan of Lanfear