Since I think that was more your emphasis, as mentioned in the earlier post Joel and I beat this horse to death about a month ago but the key point wasn't how likely fossil fuels are to form but rather that fossil fuels aren't actually even vaguely necessary for tech, just advantageous. Cars can be and have been designed to run on wood, power generation can be done on wood, coal is just handy but a steam engine doesn't really give a snot what you feed in it. Lacking fossil fuels though you must devote a large portion of your arable land to growing them... and a quick reminder that 'ethanol' is not high-tech, we've been making and burning booze for a long while, but trees or crops for ethanol, you can make fuels that are basically as good as fossils fuels for tech purposes, the difference is that where we can grow lots of crops on land without using much for fuel and indeed supplementing growth by using that fuel, mining it from infertile land like mountains instead, if you are using primitive renewable energy like wood or booze you have to devote a larger portion of your pop to tending that fuel supply and have less food for your pop. Now, in terms of tech development, I really doubt it would be a big hurdle, scientists and engineers do not make up a large portion of our society that isn't directly engaged in agriculture, mining, manufacturing, etc. nor has a lot of the tech advances been done with full cooperation, but rather often inside strictly isolated gov't or corporate research where its frowned on to send your research over to the guys who get their paychecks from elsewhere. They might go slower, but what's a few centuries compared to millions of years of evolution? and the need to use renewable energy the whole time as your growth control factor would likely cause the field to advance quite rapidly.

That's all assuming no fossil fuels to boost one up, and the natur eof fossil fuels means they will probably tend to accumalate on most worlds with advanced life, though I suppose a more tectonically active world might see the pockets they accumulate in rupture and spill out too frequently to really accumulate. All the variables tend to have possible negative and positive options though. Windier worlds, easily imaginable, could tap windmills for electricity easily, but would probably have way more erosion and say, be nothing but shallow ocean with new mountains eroding too quickly for dry land to ever really exist long enough for life to form, especially if they were not tectonically active, no big moon for instance, and so on.