My completely unjustified theory on Callandor (since there doesn't seem to be much evidence for any real theory on its use in the LB anyway).

I like the idea of Callandor being used by Ishy/Mor. with Lanfear/Sel. and Moghedian being the two females that will enter the ultimate Forsaken circle (probably the entire reason for the mindtraps to be introduced in the first place, because really have they served any purpose so far? They are a tool to help justify why any of the forsaken would step so out of character and trust one another enough to link with the Na'blis. Jordan could have left Lanfear and Moghedian in the waterboard torture room in S.G. until the LB and we would have bought into it just fine. It's not like Jordan was afraid to keep a bad guy off screen for too long.....cough cough Demandred cough.) Anyway, the net result of the flawed Callandor usage by the above mentioned could be a interesting backlash of the one power on the Dark One this time, so our wheel of time can come full circle and the Creators Taint (excellent band name) can shape the demise of the shadow for the next age much like the Dark Ones Taint did the third age.