Whilst regular Opportunist is rather useless, this has a use, albeit a very specific one. Pushing checks where you want to get the benefit for beating by 2 or more.
Opportunist is the perfect support card for a combative rouge who relies on .41 Derringer or Jenny's Twin .45s or Switchblade to do their thing in combat. Throw it in and guarantee the boosted success, and then get the card right back to use again. Double up when you find the second copy for even greater chance of success.
Skidd's and Jenny throwing upgraded Opportunist cards with one of the weapons above are effectively throwing Fight 6-7 at every opponent they come across. Excellent in standard difficulty games.
Just pray you dont get that