Personally, I think the mods need to put their foot down and start moving threads to their proper forum. Subfolders are not needed YET...not enough traffic to warrant them IMO.
Every time a post like this is made, the mods do their job and move threads for a few days, and things are good...but a week or two later and it's back to the way it was before, or even worse.
That said, there is NO way that all of the stupid, repeated questions will be stopped. You could program in a feature that popped up a message box displaying all the FAQ's about MSP's in bright flashing colors...people would STILL ignore it and post 'how much can I boost my MSP with a boost controller...i want a mad f4ster ride yo,' Every time I hear that I want to say 'Boost as much as you want, the block can handle it' (hey it's somewhat true

the block could probably handle it, but you'd throw a rod long before testing the limits of the block)
Anyways, there are things that may help.
My suggestions?
1. More moderators. This is the busiest forum on the board (well not counting the off-topic/humor/flamewars forums). If the 6 moderators aren't able to keep up with all of the threads, then more are needed. Honestly, I think adding another 4-6 moderators would help immensely.
*edit* The MSP forum IS the busiest on the board..I thought Off-Topic would beat it out, but was wrong. Also, forgot to mention that some of the moderators of the MSP forum also moderate other sections. Not that there's anything wrong with that of course, but it just further indicates the need for more MSP mods */edit*
2. Keep the 'Mega MSP info' stick thread intact, but sticky all of the threads that are linked in it. People are too lazy to look through one thread to find a link to the thread they want to see. Sad? Yes. But this might limit some of the repetitive posts.
My other comments?
Signatures and avatars don't bother me, if they bother you turn them off in your personal options.
Flaming will happen on any message board. Some people complain about 'all of the flaming here' but this board is TAME compared to most.