Spot on, this is what I have tried to say before.
People are looking for progress when there isn't any to be made! Forget all the rates of development and progress of parts before.
Everything now is a combination of factors using designer skill x number of designers allocated x level of research and then capped at the level of the designers ability.
How many of you here actually have Superb/Superb designers? Some of you might only have Good/Very Good. Or your team special skills might not be set to design, it might be commercial or pit times etc. Lots of other variables that all add up to what your teams design ability may be.
The max overall you are going to get potential wise is Good/Very Good or even Bad/Unsure with some of your staff.
You've been making parts before that might have been beyond the capability of these staff, giving an impression they are better than they really are maybe.
And the drops you see? Maybe that's just the team settling down so the parts now appropriately reflect their ability relatively speaking, as Frank said about things leveling off in time.
That's probably why so many people are seeing sudden drops and pouring money into a hole where the staff can't actually do anything about it lol.
I am not designing or producing many parts all at once either. Ever thought that might have something major to do with it all?
Focus on two or three parts at once, excel at them alone, and you'll see results
I can't stress enough, for a benchmark test put everything you have into sussing out the levels of research limits if your season is already a write off, otherwise you are pissing face first into the wind.
I hear of people using 5-8 staff on a part and developing multiple parts as well as balancing the research and wondering why they are seeing no/little progress after weeks of investment.
12 hours - 2 levels of research increase. That's a benchmark, and I bet it can change quicker if you put more staff on it!