Had a stuck seatpost in one of my bikes, tried various things but I didn’t really want to end up drilling filing sawing the thing out. So I put it in the vice on its side, tightened it up as far as I dared and just set to work bouncing the frame up and down at the head tube. I figured even a small amount of twisting the seat post would begin to break down the corrosion, allow solvent in and eventually free it up.

it worked. 90mins in the first loud crack, flipped it over and started again, 15 mins later it cracked again, and at two hours it was out, there was a good 3-4” of corrosion.

i was lucky, there was enough exposed seatpost to go the full width of the vice. Still, two hours of bouncing and twisting is hard work and I can see why people just say eff it and ape out on them.