The Rams' starters have unscripted periods against each other (offense vs. defense) on a regular basis. Live, full speed action where neither the offense nor the defense knows what the other side is calling. (That's the 'unscripted' part.) Red zone, two-minute drill, 4 minute drill, run out the clock, etc. Various specific situations are set up and then they have at it ... except they don't hit the QB and they don't tackle to the ground.
The Rams also had 2 days of scrimmages with the Ravens where the Rams' starters went against the Ravens' starters. Similar to their own practices in that they don't hit the QB and don't tackle to the ground. But they get to go against different personnel and see different schemes.
If the Rams had played their starters against the Raiders they would have gone up against the Raiders 2s, would have run a vanilla, non-game-planned scheme, and faced a vanilla, non-game-planned scheme. From my couch it looks like playing the starters against the Raiders would have been less valuable to the team than some of the things they've already done. Is there value in Goff getting creamed a couple times (or taking the chance that someone is going to go all Rodney Harrison on him)? Does Gurley need to be in the middle of a DT sandwich a few times to get ready? Maybe ... but I'm really OK with 'the plan'.
AlbaNY_Ram