You could always work around the problems belts leave behind. But, what you want to do seems impractical since horizontal springs often must be next to a solid tile so that they could point in the direction you want. Also, you could make a much more efficient system with a normal spring (you only need No Fire Zones at the bottom of the jail to prevent players from freezing the spring from the inside).

And Boggy, by the way, it's a little bit of both (although the latter with MCE's, not just simple belts).