For pools that don't show round shares, but show duration and hashrate, we can estimate the # of shares:

Total_Hash/s = (((Current_Shares - Shares_Before_Delta) * 2^32) / Delta)

Assume we compare from the start of the round, so
Total_Hash/s = ((Current_Shares) * 2^32)) / Round_Duration
Current_Shares = Total_Hash/s * Round_Duration / 2^32

And then apply some factor to during depending on stats delay...

Thoughts?