How do you guys figure? The stale shares are 2-6% more yet the devfee is only 0.35% higher.
If the pool you are mining at pays something for stale shares ( Ethermine pays .65% for a stale share ) then
you loose .35% for every stale share. But if the miner is only charging you .65% instead of 1% then it helps overcome the stale share loss.
However, if you mine where the pool does not pay anything for a stale share then it's really bad to have many stale shares.
Some pools pay something for stales, others do not. I don't know the list of which do or don't except for Ethermine.