At 41:23, after a long, long battle, I threw a 4 sec granade across entire map. In a blink of an eye right before the explosion, the granade stopped, killing 27 hp worm. Me and Vesuvio had no way of knowing whether it was 0.25 sitter or not. It felt super unlikely to have sitter when throwing a granade across 98% of the map length.

I had 37 hp worm, so what could I do? why would I unnecessarily deal damage to myself just to later find out that I didn't cow?

It was a common sense for both me and vesuvio that we simply wait to see that granade on the replay, and if my worm's health ever goes below the damage that I have caused from that potential sitter, we would call it a loss on our side.

But it never went below 27 hp, and we ended up winning, having 37 hp in my worm. After the match has ended, it turned out that the granade sitted 0.26s before the explosion.

You might say "yes, but you didn't lose a turn, that you would usually lose for inflicting damage to yourself". Well... I did lose a turn because Korydex darksided himself by building a long girder at 52:15, making himself completely immune/impenetrable.