This is a good question, and again, there is no definitive answer, the things I listed above are all factors that would affect the time it takes to go back to 'normal' .. if you have an 'average habbit' (whatever that means, I wont even attempt to define it) then it will lessen with each passing day, and I would say that within about 6-10 days you're back to being able to get off on whatever the first dose was that you took.. again, please do not challenge this figure because there are just SO MANY things that can change this time.. some people could tweak their balls off for 6 months straight, then wait 5 days and then get off on a single keybump, while others can have a weekend of fun and still be fucked the next weekend.. the goodnews is that USUALLY the time it takes to recover is low - meth is a drug thats out of yer system fast and the brain does good as keeping you in check!
Yes, of course, you recover from all drugs, it just takes time..
How dose dependant is tolerance reduction?