You have to remember, one male pollen sac can release thousands of individual pollen grains... and it only takes one getting blown in the right place to produce a seed. I've left a male in the room with flowering females before, and it was allowed to release ALL of its pollen. I can't remember exactly how many seeds were produced, but it was in the hundreds off of just a 3 or 4 females. The buds didn't swell as much, either... and left me with much less smoke. If you're wanting to just get a few seeds, instead of hundreds of them, think about flowering the male in a separate area and catching the pollen on a plate when it drops... then you can selectively pollinate certain buds, while letting the rest grow as unseeded sinsemilla. You can flower a male long enough for it to drop its pollen with just a couple of fluorescents or CFLs.