Well, true to some extent in my opinion. They will definitely benefit from extended preseason playing time and I'm a propoent of them playing several spots which inevitably leads to some inconsistent play early on. Just part of the process.
And I also wonder which rookie might benefit most from Whitworth's inevitable days off during the regular season. In 2017 it was Blythe. In 2018 Noteboom and Allen. On those days does Noteboom play LT with one of the rookies subbing at LG? I wonder how that plays out. But clearly one of the rookies will get that added experience that could then help them in 2020.
But I still maintain the Rams take a (calculated) risk rolling into 2019 with 5 of their top 8 OL having zero NFL regular season starts. If Whitworth was hurt in week one and you have Noteboom, rookie TBD and Allen as the left side of the OL that is
not a good situation. It just isn't. And if that happens (or if Havenstein or Blythe gets hurt) the sub will be playing with two established vets, not four.