How did you get to be a playtester?
My old online Dominion playtesters are mostly gone to the four winds (Jeff Wolfe is still playtesting stuff for me, and Wei-Hwa discussed the card wording with me). I wanted another outside playtester, in particular just as another data point on how fun the card was. I looked at some posters here and on BGG. LastFootnote was especially active and was still playing. So I offered up playtesting the promo and he went for it.
I play at public game nights with whoever shows up wanting to play, so that's a good way to be a playtester. Someone eHunt knows played with the promo that way.