Got a chance to try the new dynamic difficulty changes and they are still less responsive than 2.7.5.
I got some numbers this time, started up a game and ran both at dynamic intensity:
2.7.5 stabilizes during game at ~270MH/s and stays at I=6 (Game graphics only slightly different than no mining)
2.8.3 at ~325MH/s and stays at I=6 (Game graphics are noticeably choppy and playability is significantly affected)
Setting the intensity manually to I=5 results in similar performance to 2.7.5, but obviously the point of d is to not have to do that.
I should also mention this effect is noticeable in other applications than just games, like videos.
For now I am happy with 2.7.5, just thought I would post my results to help out whenever time comes to do some more changes.
The point of the new changes is for the code to not go stupid and get stuck at something really high or really low and it is
inevitable that these will be seen as fixes and will definitely be in the new code. Note the really loud message at startup saying how to tune the dynamic difficulty? Tune it if it's too aggressive or not aggressive enough...