This could be the answer.
Most tyre places will just do a tracking check on the fronts ...
Using optiline guages or similar ...
Dealer should have a full 4 wheel alignment rig ...
These cost 10's of thousands and a check up is usually therefore more expensive.
You should get a printed report of toe, camber, thrust etc angles before and after adjustment.
Should also show the acceptable tolerances ...
Last time i had this done on my IS, it only cost 25quid and transformed the car.
That was while they were doing the 10k service.
Having it done again at the 20k in a couple of weeks ...