OK, let's say we institute this cap. The obvious thing to do then is to spawn off officially-separate parties that can nominate more candidates for you. You could outlaw that, I suppose, but now we're getting into the area of things you need a judge to adjudicate, and, well... yeah.
Anyway yeah you see where I'm going with this. When I say "party", that's shorthand -- I'm not talking about literal party organizations. The teaming problem is just that having a bunch of candidates that are similar to each other increases the chance that one of them will win; it's the opposite of the vote-splitting problem, where having similar candidates decreases the chance that any of them will win. This problem doesn't require a formal party organization in order to manifest; strategic nomination is still possible.
Ideally one wants a voting system that is "cloneproof", i.e., has neither of these problems. (IRV is cloneproof, actually, but it has other glaring problems -- most notably its lack of monotonicity.)
Anyway yeah you see where I'm going with this. When I say "party", that's shorthand -- I'm not talking about literal party organizations. The teaming problem is just that having a bunch of candidates that are similar to each other increases the chance that one of them will win; it's the opposite of the vote-splitting problem, where having similar candidates decreases the chance that any of them will win. This problem doesn't require a formal party organization in order to manifest; strategic nomination is still possible.
Ideally one wants a voting system that is "cloneproof", i.e., has neither of these problems. (IRV is cloneproof, actually, but it has other glaring problems -- most notably its lack of monotonicity.)