Then Captain told me that for a cheater, knowing where the Grail is located on 111 is not a problem. And I stopped insisting on this rule.
In online play, I once dug it up on 221 on the first attempt (the Grail was underground near my dungeon capital).
In "bespredel" mode, I wanted to dig it up, but didn't even get any hints; I never dug it up once.
There was a case where, after reviewing saves, I refused to confirm defeat because the opponent started digging before 221. I told the opponent—and he decided not to file a report.
IMHO. I believe digging and uncovering should be allowed, but placing it in the Castle should happen no earlier than 221:
1) Games rarely reach 221
2) When building chains, digging with 4 heroes in one spot is problematic. Although it's possible if you have TP and DD and a huge amount of mana.
P.S. Naturally, I am against cheating methods for uncovering.