The only way the train works in this TdF is if they push so hard that they get the group of heads of state down to 10 riders, 3 or 4 of whom are Ineos, and Roglic and Pogacar are by themselves. So they can then play their cards.
Seems unlikely imo that you can ride hard enough to shell all of WVA, Kruijswijk, Kuss, Majka, Formolo, McNulty, Vingegaard etc without putting the likes of Carapaz, Porte or Thomas to work. I can't see TGH, Dennis, Kwia etc dropping them easily assuming those guys are timing themselves for the Tour. You also have to hope other teams like Movistar or Bahrain won't chase you when you attack if Pog and Rog are isolated.