If you're powered up like that, try just letting go the clew before entering the jibe entirely. If you take enough speed with you in the entry you can easily fly through a jibe with no power in the sail at all. If you want to, you can try practicing half jibes downwind while only holding on with the fronthand!
For the rest, if you want to jibe using a little more power or in a little less wind, I think the 3 main tips:
1. open the sail early! Yes, still, you dont have to let go, but you want to open up earlier than a regular carvejibe!! If you open the sail too late you'll get "backwinded", which means the wind will push in the sail from the other side.
2. keep the sail well away from you and use it as a counterbalance. If you shift your weight to the inside of the turn to carve, move your sail more to the outside of the turn! (This is the same as Berowne's "backhand in front of your face", except you want to do this with outstretched arms, almost feeling like you're toppling the sail forward.)
3. In the beginning, try to keep your weight over the board. You dont have to carve hard to make the turn. Staying on top of the board during the carve greatly increases your chances of succes, because you'll have more control over your rideheight when you stay on top of the foils' power through the turn. This last point is a key difference between a foiling jibe and a regular carvejibe. If you look at this video you'll see I'm completely on top of the board, only lightly carving and with my weight centered instead of really leaning in the turn like I would with a carvejibe. (It was over 30 knots in the video, so its a little wobbly)
www.instagram.com/p/BuzGrhQIRyE/?igshid=47ylbe5383vfI really like this video of Wyatt Miller, you can see he also stays very much over the board and only slightly carves to get the board turning. In the video he is doing duckjibes, but his worded explanation is on normal jibes, it doesnt really matter that much either way, because the footwork and carving is very similar for both, and all you have to do with the sail is let go of the backhand very first thing.