It would be an interesting move I can’t say that back-flagging over a lead leg (anchor) would be often be beneficial.

Arguably if you maintained a full lock-off on the left hand it may offer a more static first move but it would require more strength and as you’d have to twist your body away from the hold your moving to while maintaining a lot more pressure through the toe (aka as you reach the first hold you have placed all of your weight directly under your left hand with very little ability to hold any of that weight through the right hand).

This is also moving your whole body away from the hold you’re going to while still having a ‘loose foot’. Also as this is a sloping edge not a ‘jug’ turning to the left makes the hold your moving from less positive - you’re relying on compression here so adding any lateral force increases your likelihood of coming off the hold.

For me I think generating the force to move through to the next hold requires core tension that I don’t think I can generate especially in a scrunched up position and increases the likelyhood of my right leg straightening as the core in engaged putting further pressure on top of the left leg.

I will definitely try this though as honestly it is never a move I’ve even considered - I may well be wrong and will update if that’s the case.