Sir Valiamont, I can see where you are coming from. But really, you are confusing people, because in general, you refer to 'desyncs', which are associated with bad connections ect. But what you are really reffering to is intentional desync when you talk about opponents changing cards based on your deck, or 'desyncing' until they have a perfect hand.
I too suspect someone of doing this, as we played 5-7 games(mirror matches), most of them very short, and I lost 2-0 (If you recognise yourself here, It would be wise not to post as you are deliberately being left anonymous). I don't often have huge problems with desync, so this struck me as slightly suspicious, as the next time we played, I deliberately used mediocre decks, and we played 2 only games (no desyncs), and I lost both times again.
However, there was really no way of proving whether it was desync or not (no desync warnings ever showed up, just timed out and left to play computer before it was obvious a winner could be chosen, but after initial hands were played).
Of course, it may have just been bad connection that day (although my other matches went fine). I have not acted upon my suspicions (as you obviously have) as that is all they are, suspicions.
(again, if you do recongnise yourself here, claiming so will only raise suspicion. I will NEVER reveal your name on a public thread)