lookin good man.
these little green things are pretty amazing plants. you can chop them, shock them, burn them, and treat them like an abused puppy.. and like that puppy, with a little love, they will bounce right back.
if you want to play around with chopping random shoots, leaves, whatever. giver. how it reacts helps you better understand them.
i SUGGEST, leaving the fan leaves if you can, just tie them back so the bud sites get more light. Fan leaves act as your motors. without them, your plant wont grow to its full potential.
i do like the fact you trimmed underneath, i do that too, and they love it. plus, in my little setup, those leaves dont really see much light anyways, and will eventually die off.
that discoloration looks fine. if it progresses into something else, then diagnose it then. its better to neglect them, and get a slight deficiency, than to love them too much, and overdose/burn them. a burn/overdose is a LOT harder on the plant than being a bit hungry.
make sure your PH is set, dont overfeed. and dont worry so much about them.
it almost seems, the more you neglect, the more they want to grow to grab your attention
good luck, and ill follow along.