6 blocks each hour is for the whole network.
For the pool only just calculate 3% out of the total pool speed = 3% * 2700TH/s = 80TH/s
So 80TH/s is around 28 btc per day at current difficulty. But because there are people using PPS, it is more than 30btc a day.
Now imagine what it was 2 difficulty retargets ago. Probably around 50btc a day
Subtract 1% from the 3% fee for orphaned blocks, which are roughly 1 in 100 blocks. And PPS is barely over 10% of the pool now.
And don't "imagine what it was 2 difficulty retargets ago", because BTC Guild was not 2700 TH/s 2 retargets ago.