I did, from time to time. (Of the "do whatever is best" variety rather than the "do whatever is nastiest" variety.) Of course I can't be sure how thoroughly I meant them.

It would be easier to believe in a link between "dangerous prayers" and deconversion -- at least, the sort of link I think you're suggesting -- if there were more sign of people praying such prayers, getting God's face hidden from them, and having something wonderful somehow come out of it that wouldn't have been possible without the face-hiding.