I remembered another snippet, or tidbit, (or snip-tid, or tid-snip, or...?) of trivia to mention.
I wore a brand new, never been washed, dark green pigment dyed t-shirt on Monday. On Tuesday morning I realized it had dyed my armpits green! And it didn't even come off in the shower! Only some serious, and slightly painful, scrubbing made any impact at all.
Lesson learned: never wear a brand new pigment dyed shirt without washing it first.