hey man! i never actually realized it was you! and hell yeh you should be proud of your grow, its a little beauty in response to ur first question, nah i havent planted the Jack Herer/HOG seeds yet, im gonna wait till spring as jack herer is a real bitch to grow, (according to other ppl on here) and at the moment its autumn, so im in the process of making and outdoor plot.
In response to what you said about your plant it looks as though youve got a real survivor of a plant there, personally i see nothing to worry about, although i know how discouraging it can be when your plant reverts back to growing three blade leaves, you shouldnt worry about it too much, the stalk going grey seems to be a sign of its age, and i must say it does look like a pretty mature plant, so your okay there.
Now if you want more growth on the lower parts of the plant ive heard of a trick people use sometimes but cant remember what its called, basically you use something to pull the plant over, making the top face downwards, you tie the stems together like that in order to release a certain hormone in the plant which induces growth in the lower parts, making them grow, now, its kinda hard to explain it on here and ive never used it myself and have no idea how well it works, but if you can read up on it online to find out how to do it as safely as possible, and you think its a good idea, it may be worth a try, whatever you do, let me know what happens please.

Peace mate, and good luck with your plant