My hair is just past shoulder-length, and I'm looking for waist-length someday. I know you're suppossed to cut off any 'very damaged hair' before you can really start growing, but what qualifies as damaged? My hair is level 3 permanently dyed red with black tips. But it looks and feels healthy, especially after I started following advice from LL. I don't have any split ends somehow, even though I haven't gotten a trim in ages.

I only have about half and inch of 'virgin' hair at my roots. PLEASE don't tell my everything with dye has to go?

Well, the dye will remain in your hair so if you want to return to your natural color you will have to cut the dyed hair off.  I recommend going to a salon and having a color specialist blend your roots so as it grows out you won't have to continue coloring it.

So, trimming an inch every couple of months will help you get rid of the dyed hair and you won't loose too much length.  Of course, you won't be adding much length either but after the dyed hair is cut off you're home free to grow as long as you want!