F2pool is a completely different type of pool than flypool, or any other pool you're likely to find. The pool itself absorbs the ups and down of the pool's "luck", i.e. you get a consistent payout regardless of whether the pool "luck" is positive or negative, which is why the pool fee (3% for ZEC) is so high, relative to other pools. Therefore, if you compare it to another pool, and that pool's "luck" is negative at the time, it's always going to look worse than F2pool. In addition, flypool, just 2 days ago, finally implemented the common "immature payout" scheme that most pools use. Prior to that, payouts were real-time in that you were paid based on blocks that had received 120 confirms. That method had the side effect of miners being able to "see into the future", since it was already known when the pool had a large number of blocks to payout in a given hour interval. This was causing massive pool hopping, where rented hash was hitting the pool on every big payout hour, then leaving, which diluted the payouts to miners that were on the pool when those blocks were mined. That is no longer the case.
Common sense should tell you that if there was that big a disparity between F2pool and flypool, every ZEC miner would leave flypool and mine on F2pool, and yet flypool has been, by far, the largest ZEC pool almost since day one.
Finally, the logic posted here seems plainly flawed, to me. Of course you receive a smaller portion of the block awards on a large pool compared to a small pool, but a large pool also mines a shitload more blocks per hour/day than a small pool. On a small pool, you are getting a larger proportion of a small pie. On a big pool, you are getting a smaller portion of a big pie. The large pool also has much less variance in the number of blocks it mines per day, compared to a small pool.