Second project

that's a 90W grow light in a 2x2, its a bit under-powered but it will get the job done. Ideally I'd like to see at least 120-150w but I have used 90W before in a smaller tent with fantastic results. If by teaching plants you mean training I would look up something called LST or SCROG'ing. these are methods used to help control the spread of the plant in a space so it is utilizing the light and area better. In a nut shell its making the canopy even in hight so the lights hot spots are minimized and helps with even growth then spreading the growth out to all corners of the tent to prevent wasted light. Good Luck!

For a 60X60 tent you should only have 1 plant when they start flowering. even then it will get tight with a height of 160cm you gonna get in trouble if the plant grows to an average height for 2 flowers i would reccommend atleast 80x80x180

Work backward from your end goal and make it happen. Shoot for 2-3 colas per sq ft. you'll have to do the conversion to metric :P any "technique" that invovles stripping away a ton of leaves and such typically take longer due to over-stripping leaves. Be patient to remove leaves. have a good reason. You can remove an axillary bud and let the accompanying leaf remain. you have several tools. use any combination. Breaking apical dominance can be done in several different ways. Sometimes, it's better to use one than the other, but for the most part they are equivalents. The plant will grow at the rate it's genes allow and assuming you don't step on your toes. Our contribution is more about not screwing up and 90% is just the plant doing it's own thing - no matter what the marketing people say. keep it level.. slow the shoots down that are outpacing other stuff temporarily until the other stuff catches up.. rinse and repeat. bend it, tie it, cut it.. whatever is best for the context. LST, topping.. all good. using a scrog is nice for larger plants. sea of green will reduce vege time, but then you need a ton of smallplants that come with their own added efforts to maintain. No matter what you'll need the same amount of light per area and similar amount of effort/maintenance no matter what you choose to do. you'll eventually run into some floppy plant at some point, the screens/trellises are good to use just for that reason alone... trying to tie up a bunch of limbs with wire or string is a giant pain in the ass.

Look at my profile mate. I use a similar size tent to you. My newest diaries are quite detailed as to what I do to control stuff. I been growing quite a while and I must admit when I started to try out autoflowers I struggled quite a lot. No where near as easy to manage as a photoperiod. Don't get me wrong autos are good for me outside.

I recommend you put the Auto's outside where they belong and stop feeding the seed breeders with cash.