Well, I reckon FDJ will "honour the jersey" and keep the break in check. Roglic will say thank you and take bonus seconds at the end. Rinse and repeat for the rest of the week and no one will do anything because "It's a three week race, gotta balance your efforts, yadda yadda". Then, after next weeks ITT, Roglic will be ahead by 2-3 minutes and everyone will suddenly wake up from hibernation and wonder how could this have happened. But given that this isn't the Giro with ridiculous backload, people will come to the conclusion that they have to settle for second and third and chase each other down endlessly.
Yes, I'm a pessimistic doomer, Roglic might still not feel 100% so I guess there is hope.
Honestly it sounds like an accurate description if one isn't into Roglstomp