I agree with Marsha C. This harness (you will notice that its design does NOT incorporate wrap straps) allows the shafts of my easy entry cart to "float" just a tad more than I am comfortable with so I often use both breeching and thimbles, but I use and adjust them in a manner that does not put constant pressure on either the breeching or the thimbles.
In my opinion, thimbles should not be used in place of breeching except for extremely short, extremely "controlled" (in an enclosed area with extremely flat footing) drives. I do not like that the current show trend seems to be using no breeching, but I will drive that way to remain competitve only in the ring with the use of thimbles and/or shaft stops and I would like to give false breeching a try in the future.