Final Potzie Rootbound Flowering Help

hi i heard when i switch to the 12/12 cycle i should have allready potted my plants into there final pots and let the roots grow out till i can see them at the bottom of the drainage hole?is this true if so can someone explain will it not get rootbound during flowering?please someone explain what they do when they pot up to final potzise.

Being root bound is no big deal unless you've got them in a party cup. It just means that the plant won't get very big if it's in a small container. The bigger the container, the more roots, the more leaves, the more bud. If you have a small flowering room (or tent, cabinet or whatever) or you just want small plants because of space or light issues, then you use this to your advantage.