As the Listmeister once counseled me "Patience, Grasshopper"
I have heard some good hints, especially the use of Kroil. My good buddy Karen Rawls counseled me early on about using patience. She pointed out that they will all loosen.eventually. Prior to that I have torn the ears on a seat post clamp by excessive zeal in twisting and also bent a fork when holding the wheel between my legs and twisting on handle bars to loosen a stem in the past. If I had been a bit wiser then as a beginning restorer of bikes (or sought Karen's advice sooner), I'd sure have saved myself a good deal of trouble.
At any rate, I'd say to one with stuck parts that to rush things.and a month of soaking is not unheard of. is to invite disaster. It really is amazing how much damage one can do to a bike with a premature and undue excess of force .even just using one's hands and arm strength.
Tom Sanders
Lansing, Mi USA