Right, so I have a Togepi I’ve been grinding up the level/friendship of, and it has the ability Serene Grace, which doubles the odds of any additional affect occurring from a move (such as flinching from bite).
I must have used Secret Power somewhere between 15 and 30 times. However, it has never once triggered that I can remember, which should be 60% of the time after Serene Grace’s doubling. I also have never triggered the secondary effect of Ancient Power, though because that has a 20% post-doubling chance of occurring it’s much more likely that I’m unlucky there.
Not sure if it’s Serene Grace in general, or just Serene Grace with Secret Power, but something is probably going on here. If someone else could test this to make sure I’m not going insane, that’d be really nice. I mean, it’s triggered occasionally when used by other pokemon I have, just not Togepi!