My question for Mitch: What is the suggested length to leave a beer on dry hops? What is also the maximum length of time (days, weeks, month, etc.) one could dry hop for? I've heard varying preferences from brewers from anywhere between 4 days to 2 weeks. Will leaving a beer on dry hops for 3 weeks really make a difference? Obviously, tasting the beer is one way to tell when to rack off hops, but I wanted to know if there was any set standard to abide by. (For the record, I haven't bought or read the new IPA book yet - in case this is covered within the book.)
In addition, what are the deciding factors besides "time" for when to rack off hops: %AA, total hop mass, leaf/pellet/plug form, temperature, etc.?
I wonder if dry hopping is sort of like the old idea of racking your beer off yeast to prevent autolysis and off-flavors from developing. Similar in vein, will leaving a beer too long on dry hops really give you harsh hop qualities, or is this just a perceived threat that's been passed on from homebrewers over the years?