Well, my alarm didn't go off this morning, thwarting my plan of giving an update before leaving home. I'm at work right now, but I'll give a brief update and possibly a movie when I get home.
For starters, I tested death-glitching the tank. It might be possible to shave a couple of seconds off of the boss by having the ice wall drop into the boss and you dying; creating the ice wall to damage the rear component. Basically, if you create the ice block on the component and die the frame afterwards, it's 8 frames slower. You basically need the ice block to live longer, and only creating outside of the tank and having it fall it could do that. I suppose it's possible to do, but at this point I'm too far along to want to try.
I did redo the flying mid-boss and improved a surprising 4 seconds. Most of that was actually hitting the boss much earlier; I better understood how the drill does damage and realized why my previous attempts to damage it failed. I also optimized the death glitch really well. :D
The death glitch doesn't work against King, but if you're fast enough then you can have text on the screen when you respawn in the 3rd mini-level. :) Interestingly enough, the final battle against King had the same glitch as Bass from Mega Man 7; the last hit deals damage to him even if he's flashing. So, basically I only had to hit him 5 times (which is good; I took a lot of damage in order to hit him as early as possible.)
I'm currently just at the Magic Man rebattle in the final level. There's a problem, though. Up to that point in the stage, my Tengu ability went to 8 bars at the lowest, meaning that one of the energy capsules I grabbed before is unneeded. I'll measure the one before King and the one before Pirate Man with the hope of not having to start over with King to fix. I'll probably also experiment with hex editting to see if I can fix it, but I'm not very hopeful about any of these panning out well. Since this error is so obvious, I don't think I want to submit with it in there, either.
I'll try to remember to post the latest movie when I get home tonight.
Edit: Uploaded:
http://www.kraftfam.org/~erk/nesvideos/RnF.zip