if you have to yank them with a jack or a tractor they aint rotted so bad they wont keep in goats. If they are rotted enough to snap off, then you usually can auger rotten stump out if you have 2 man post hole digger/auger, or a tractor, then reuse that rock hole. I know what you mean, i have to spud bar holes in sheetrock sandstone/limestone. not fun, but you never need cement! thise t posts are a PAIN to drive into rock, and if you wnt them out, goooood luck pulling hammered t posts out of solid rock. iF I were you i'd sell the t posts and buy wooden posts, cured locust wood posts if you can get them, and soak the hole ends in foundation coating and let them dry before ya set them again. you wont have to replace them in your lifetime. there are locust post fencelines around me that have to be 50 yrs old...and the posts are old but useable still. if no locust you can buy wolmanized posts for the same price as the tee posts or cheaper if you buy a truckload, and those wont rot either. i bought a truckload of about 200 posts 20 yrs ago, they have a lifetime warranty (my life) agaist rot. ive pulled up some and reused them, and none are even the slightest bit rotted.
not to mention, if you get a horse, t-posts are giant skewers waiting to happen.
there is one trick to setting them strieght... a jack hammer. you can rent or buy a bosch electric jackhammer, with a point bit (a long one) and pre-jackhammer the holes in the rocky ground. A friend of mine showed me how to do this as he was wire fencing off his garden, and under the topsoil is sheetrock. we set 100 t posts with no trouble in one afternoon. the damn hammer weighs a ton but its EASY setting those t posts. it hammers a 2 foot deep hole about as big around as a shovel handle in about 15 seconds, if the rock is like ours here.. just drop the t post in the hole and jackhalmmer a few holes around it to set it.
warning... youll hurt for a week, but youlll hurt worse using a hammer.. and your posts wont be strieght.
hope that hillbilly handyman wisdom helps..
"if the women dont find you handsom, they should at least find you handy"