XAPBob wrote on Tue, 03 June 2014 10:29

do we want to encode the additional flexibility that the original code has (but never exposed) of having an "off centre" perfect (so you get a short tail on one side and a long tail on the other?) I think it's probably easier to add it in later if needed.

I'd like it, as long as it doesn't take too much time to do. Alas, we don't have real-world test-cases for it.