If I had to score them out of 10
Hyperinflation - 1/10
n^2 - 2.5/10 (this appeared to have worked better because people weren't as sophisticated back then and abit and smooth were incurring some of the costs of making it work better than it otherwise would have)
our current system - 1.5/10
I think we can do maybe a 5.5-6/10 on our next attempt if we frame the problem correctly and identify both the benefits and costs of each of those measures to reach sensible numbers.
That was only for a relatively short time in order to demonstrate some of the negative effects of unrestrained n^2.
For most of the time it didn't really work at all, and people claiming that it did either weren't around at the time or were out of the loop and didn't know what was actually going on.