Ah yes! Accounting for that, if I'd just held the original BTC I paid in, my pool profits compared to that (in terms of BTC) are only 5.8%* which I guess is much more reasonable for the pool operators.Did you factor in that you paid with pre-fork BTC, which contained equal amounts of both post-fork BTC and BCH?
Still though, I have a month of earnings to go.

*As of the exchange rates at the time of my original calculation. Exchange rates since then have changed.