What's hapen if a multipool mine at 271 for 1 block. then stop mining the next one  who go to 350. Then mine the next who down to 272 ?

Its possible that ? or DGW prevent that ?

I'm really happy with my current implementation of DGW, it seems to be vastly improved over KGW. It uses multiple exponential moving averages and a simple moving average to smoothly adjust the difficulty. We've had huge fluctuations in testnet and it's dealt with everything perfectly.

This implementation also fixes all known exploits with KGW, so no more 10k+ difficulty blocks out of nowhere.