Okay, so it's been a week since that post. I had completed Astro Man's stage either that day or the next, but I only today worked on the boss fight itself. About buying the half-energy-for-weapons item, it took 375 frames to buy and equip. Each t-dash saves about 10 frames per use. So I only need 38 extra t-dashes in order to make up for buying the item. The verdict? Very easily done...each level starts me out with an extra 14 t-dashes, each big weapon capsule gives me an extra 4, and each small an extra one. So, after Astro Man's level I've received 22 extra t-dashes. I expect to surpass 38 extra by the end of Dynamo Man's level.
For Astro Man's stage there's a couple of things to point out.
For the two ordered-button rooms (IE, buttons flash in a certain order and then you press them in that order) I experimented with luck to get some fairly optimal combos. Granted, getting the same button all the times would be best and preferred but would probably require a lot of excess shooting (guestimating 27 shots to optimize first room, 243 for the second?). The pattern is pretty simply determined; the first is randomly selected, then the second, then the third, etc. Shooting looks to be the only way to manipulate luck. Shooting a small shot (IE the small shots when you have an Ice Wall out) seems to read the next random number and dump it. A normal purple shot dumps two random numbers. This became pretty apparent when I tried searching for an optimum pattern:
0 - M R R M R
1 - R R M R R
2 - R M R R R (1 norm)
3 - M R R R L
4 - R R R L L (2)
5 - R R L L M
6 - R L L M L (3)
7 - L L M L M
etc
Also, you'll probably have to look at it slower to notice the t-dash glitches. Basically, once you dash with the Tengu weapon equipped, you can switch whenever you want, but if you hit something the "slashing" graphics become funky. In particular it picks up the graphics of the current weapon.
Anyways, all that said, the latest version is up:
http://www.kraftfam.org/~erk/misc/RnF.zip