
This is worse than 'Unexpected Courage' as a standalone card. You just can't consistently time important checks to get that extra '?' icon. It isn't hard to use it with two icons though, so it's not that much worse.
But unlike 'Unexpected Courage', 'Prophesy' can be tutored by 'Practice Makes Perfect.' An investigator with access to just the seeker and mystic pools has a pretty shallow pool of practiced skills with 'Perception' and 'Deduction' as the obvious standouts.
With 4 targets in a 30-something card deck, the odds of missing a search with PMP are significant—especially if you've already played PMP once. So if you want to be sure you won't waste that card and possibly fail the skill test, 'Prophesy' is a reasonable addition. For my part, I've done this in a Mandy Thompson deck and have not been disappointed.
I wouldn't look at this card in any other situation though.