I recall reading (or viewing) that in many situations the anchor doesn't actually play a part in controlling the position of the ship. Instead it is the weight of anchor chain dragging on the sea floor that dictates how much the ship can move.
As a result, when the current direction changes on an anchored ship, the ship has to be prepared for motion as the ship traces a path over the anchor chain.
I think a ship can drop one anchor as it drifts in the current until it has let out a lot of chain. Then the ship can drop another anchor and take up some of the chain on the first anchor while letting out chain on the second anchor.
In its final position the ship would have to drag one or the other chains in order to move.
Freeper sailors feel free to comment.
The chain is much heavier and does most of the work. I used to be really addicted to Deadliest Catch and there was an episode in season 4 or 5 I think where a really nasty storm was hitting the crab grounds and Cpt Hansen gave the camera a bit a tutorial on anchors. He took the ship into a bay where it would be in the lee or a mountain on an island and dropped anchor. And he talked about how the chain is actually the important part, and all it was really going to do was reduce their storm drift. But even then, with a much smaller ship and therefore a much more favorable anchor and chain to ship weight ratio he didn’t expect the anchor to make the ship not move, just not more FAR (mostly to keep the back end of the storm from pushing them into the island).
You really can’t use anchors to stop, especially not when the ship gets this big. There’s a reason big ships get the right of way, changing anything about their movement is so hard. 100,000 tons is a lot of momentum. Nothing relying entirely on drag is stopping that quickly. You need to push backwards.