I'd be much more careful with statements to the effect of McLaren and Ferrari getting faster every race compared to Red Bull after a couple of races whose characteristics didn't suit Red Bull.
I'm just saying...
It's a very valid point, and you're right that it needs to be factored in. It is only my opinion in the end, but, I think Valencia will show us a lot. It is a track far more suited to Red Bull and it is before the complete overrun ban comes into place at Silverstone.
I guess we shall see.
At Valencia, the equation changes quite a bit with the engine mapping changes in parc fermé banned. Thus, it could be considered another track not well suited to Red Bull - this could be the case for all races still to come until AN has pulled out another rabbit from his seemingly bottomless hat of tricks. Hence, it's going to be interesting to see what happens, but again, it won't be the last word. The next major change will come in Silverstone and from then on we can hopefully enjoy watching the engineering chess game of development to the last race of the season w/o FIA's heavy-handed impact.
The parc ferme change will only effect RB's Q, there won't be any race effect until Silverstone. So, whatever advantage they have will still be there in the race. As I surmised earlier, I think both Ferrari and McLaren will take another jump forward in race pace while any gains RB may make will be somewhat lesser.
I'm really looking forward to seeing race pace at Valencia. Red Bull still with their overrun capabilities and Ferrari and McLaren with their improvements. Hoping for another fascinating race.