I've been letting one of my better performers (what do i know, though? first time.) veg for quite a while under 24/0. It's growing nicely. I was noticing what I thought to be either pistils or stamens. But 'no way' i thought, as they'd been under 24/0. Today I noticed that they are starting to look like the first set of true leaves after the cotelydon. Should I let these branch out? Will it be beneficial? Will this possibly increase yeild or the number of budsites?
Once you've vegged long enough, nearly every strain will show its sex. The growth you're seeing above the cotyledons is eventually going to be a really, really small bud site. I trim off my lowest few bud sites before flowering so that energy is dedicated to sites that receive more light, but this process is not necessary. If you enjoy watching the new growth, by all means, leave it.