Yes... this problem is well known.
Especially the very old torsos from 1978 to approx 1982 are vulnareble to splits. And it always hits the torsos with the best looking patterns :-( (The bat lord torso in the pic is intact.)
I hate the cracks. They don't stick to the legs very well (especially when the legs are connecte to something). Also they make the arms loose to. This sometimes happens with the arms of the minifigs too. What should I do? Tape? Glue?
Tape looks awful. And glueing doesn't help much as long as you just glue along the actual split. Each time when you move the legs into a new position (sitting, walking etc), the glued split will breake open again. You'd have to glue the legs into the torso. That means you have to make a final decision on which trousers the minifig has to wear for the rest of his life. And how is he supposed to use the toilet?