First, I absolutely believe that an increase in the blocksize limit is not necessary, at least in the next six months and before seeing somethings about how seg wit plays out, after seg wit goes live.

However, I thought that almost all non-emergency changes to bitcoin's protocol can be achieved by soft-forks?  In other words, I don't understand why a hardfork would be necessary, if the only change was to increase the blocksize limit from 1mb to 2mb.