If they are going feet first at a retrieve object, they are avoiding picking it up.
I think it's more excitement-chase-play stuff....
My Bertie used to do this. It was puppy play stuff. It showed he was excited about getting to do the retrieve. But he'd jump in the air and POUNCE on the dumbbell.
We started putting the dumbbells slightly under ring gating, up against walls, having a training partner put their foot on one of the sides... and the pouncing stopped. I don't force fetch so I'm not sure how that would fix the issue.
It doesn't mean you get rid of the desire to retrieve. I did a fun match yesterday and we were working on stopping anticipation for the retrieves. Bertie was taut and sort of twitching/vibrating waiting to go all shot out of the cannon after his dumbbell when I finally told him to jump.
This dog has very clean and careful pickups now even though he started out with very flamboyant pounces.
As Anney said - you want to stop the pouncing if you don't want to lose points. Same thing with flipping, mouthing, fumbling around with the dumbbell - all signs of an overexcited retriever, but stuff that will cost you.
*** Meant to clarify. The dogs don't generalize on this. Bertie still pounces when retrieving toys or sticks. He knows when he's working in the obedience ring and when he's not.