Yeah do watch/listen to the very good Haskell podcast with Dombrandt on this
He says last season they moved to far less contact training (sometimes only a few minutes a week), more days off, no captains run (pointless energy sapping waste of time is the verdict - as Haskell says, its one of the “traditions of rugby” that seems of no benefit to anyone in 2021 and best suited to life around 50 years ago).
They agree they could never had understand why you’d choose go into Saturday exhausted.
Dommers credits the changes to them becoming the fittest team in the Prem, able to outlast most others etc