Playing for muscle strength/dexterity?

[jvizzlez]

I've been training on SM for a while now, and I'm able to play, at most, about 320 BPM 16th streams such as Massacre on HSMP12, Wrath of the Hedgehog, etc., but I've been starting to plateau recently.

To remedy this, I've been playing speedfiles almost every day for the past week or two, and only now have I begun to question my method... should I train my fingers like I train when I do other exercises -- that is, every other day? Or should I keep on mashing until my fingers fly out of their sockets and kill someone?

And how about sightreading? I play at C1000 for moderately difficult (6-8/10) songs, and drop that down to C900 for the crazy songs. Files like 8th Era seem utterly impossible and even at 0.8x speed, reading them is fairly difficult. How should I go about training my "eyesight", if you will?