From what I understand Ten Hag latest 3-1-6 tactical plan, in attacking, he is heavily relying on pressing, hoping opponent player for making errors and thus we can create opportunity.

The cons of this tactics is that it need lots of hard working players to press and it also consume lots of stamina.

Hardworking is exactly what most our players lacking of, may be that is why he wanna buy Mount, and insist to play Antony.
But then if that is what he wants, then I dunno know why he sell Fred, our most hardworking player.

Stamina is also another general weakness of most of our players. We have seen it again & again, our players played well in first half, but dropped dramatically in 2nd half, it is due to stamina.

And now Ten Hag still wanna apply tactics that require even more stamina? I just don't get it.

The tactics fit team like Brighton so well though, because most of their players are pragmatic energetic players.

For me is like this.
If we have fish then we cook fish.
If we have ayam, we cook ayam.

Now what I can see is, we have fish only, but Ten Hag wanna cook wagyu.
The taste? Sure awful la.
Then some fans blaming that the fish is awful, not tasting like wagyu at all.
For me it is chef problem.

I hope your trial and error theory is correct.
So now he see his 3-1-6 tactics is totally unmatched with our current squad, and will change it.

He may look for 3-1-6 tactics in long term, but currently we just don't have sufficient players to fit the tactics.