So far Johnymax has come up with the explanation that's most plausible to me: They had a plan which would have put them in a comfortable position if it had been executed perfectly, with Vingegaard winning the stage and bonus seconds and Roglic not being far behind.
I wonder how they estimate the riders. Maybe they rate Vingegaard higher than me (although I have him on my cq-team, so happy to be wrong...), Roglic worse than me, Pogacar higher and McNulty worse.
I still think I'm smarter than Niermann.
There are two things about which I agree with CyclistAbi, though: It was a deliberate decision by Jumbo and Saturday we will know more.