Seems to stop growing in bloom.

Yes, just wait it out.. keep them healthy, of course, as you normally would react to what you observe. i would try to fix whatever is causing the chlorosis in top leaves -- possibly too much light (nodes are a bit tight recently) or possibly overdose of p/k can do that too - that would usually coincide with thinner blades, too. Stem elongation and leaf growth (a.k.a. vegetative growth) will normally stop around 4-5 weeks after flip to flower. This varies a bit per seed. Various behavior may cause it to vege longer or shorter than normal* (*for that particular seed)... It's not in perfect health, but doesn't seem significant enough to have a major impact on when it flowers. I'd wager this is merely genetic diversity. Unless you caused a great amount of stress, the other plants may just 'stretch' more in flower. keep the leaves in future. leaves should only be removed for very specific reasons. They perform numerous functions beyond absorbing light. They are also room for error for all sorts of mistakes. REducing leaf surface area, even if shielded, reduces ability to take in CO2 which is one of the biggest limiting factors of growing. It'd be damn hard to overcome any reduction to transpiration. This is your typical bro science.. unsupported claims for techniques that do 'amazing things' that nobody has successfuly measured or proven to be true... just blind faith in it and a belligerence directed at anyone that contradicts these poor hypotheses.