I've been playing on this server last 3 years with over 11K games played. I have never seen players like this... https://lichess.org/@/VRK/perf/blitz
Highest rating: 2252
26 Mar 2020, 14:27
Lowest rating: 800
29 Apr 2019, 10:44
I find this extremely suspicious. I find it very hard to believe that an 800 rated player can achieve 2200+ in less than 1 year even with a personal chess coach.
And the same goes for this player here https://lichess.org/@/Dawista77/perf/blitz
Highest rating: 2066
5 Nov 2016, 09:09
Lowest rating: 1356
13 Jan 2019, 01:51
Best rated victories
FM jposthuma (2340) 1 Jan 2017, 09:41
Worst rated defeats
tilucp (926) 3 Aug 2018, 14:32
Seriously, there is absolutely no way for a player to have such huge rating differences and worst defeats against players below 1000 rated opponents all the while being able to defeat a FIDE Master. Without actually deliberately losing to make their ratings poor, this is virtually impossible.
The most obvious is the second player. He cannot be achieving 2000+ in 2016 and then 3 years later have his rating performance deteriorate to such an extent that it drops to 1356.
Once we genuinely achieve a certain rating you really can't drop that low unless you have brain damage or some sort of alzheimer's disease or dementia.
I'm not trying to be discriminative and say it's not possible for a poorly rated player to improve. But here we do not see natural improvement or deterioration that can be described as realistic. Modest variation is normal or if the rating increase can be seen after a longer length of time where the player is able to prove that he/she really improved.
We know there are cheaters who deliberately drop their ratings so they can enter low entry rated tournaments and win against those players. So that way a stronger player is artificially winning tournaments against weaker opponents due to sandbagging as described in the FAQ.
Sandbaggers should be banned from participating tournaments and should have a marker in their profile that states otherwise.

