I totally agree with the OP. Those signature bans are not working out, stupid idea, let's go back to permabans - lets bitching that way.
Or the mods could decide to permaban someone (based on the quality (or the lack of quality) of his/her posts), or to give a second chance (sig.ban).
It's alway better to have a year sig ban, if you have an established account, because you would miss only one bull run, but you don't have to start you account from scratch...