SOG to veg or not to veg

When doing a SOG, do you still need to veg for 1 or 2 weeks (or 4, or whatever it is), or can you grow 12-12 from seed? What's the right way of doing it? I've heard both opinions, but I want to know what works better...

Only way to sog is to run mothers and operate in a perpetual style eg, I have separate mothers / clone boxes and preflower rooms and a 4x600watt flowering room. I operate in a 2 week cycle so every 2 weeks i take clones. They chill in my 150psi misting clone box for 2 weeks then move into 1 weeks of veg concentrating on the root growth then 1 week 12/12 before moving into flowering room for 8 weeks. Heaps of work tho. but I need seeds and currently not growing

I would say it's strain-dependent. Best bet would be to flower out each strain and see how much each stretches from the original size (2x? 3x?) But if you don't have the time or patience to get to know your strain, I would probably veg out indicas a little, and not veg out sativas out at all.

But again, it depends on how your strains stretch and fill out over the transition period. I have some that I can put in as clones, and they can fill out a 2x2ft space easily, and others that will just produce a single cola...those I can cram in like 15 into a tent, where as the 2x2 style plants I can only put in 3-4. So to avoid having to kill some later because of overcrowding, it would be best to know your strains.

TLDR: Some do 12/12 from seed, but I would recommend taking clones, learning each strain, then planning your tent around each of their characteristics'