My father-in-law’s garage told him that it wasn’t necessarily bad to rotate tires, but that each rim should always stay on the same hub. I told him it was the dumbest thing I ever heard. I can see the logic - slight differences in the machined surfaces might grow to conform to eachother, but I bet even Formula 1 crews don’t worry about this. Has anyone else heard this before?
Maybe he needs a new garage. I wonder what other strange ideas they have.
I agree that this is very strange, as well as incorrect.
Apparently, these guys believe that they know more than the engineers who designed the car.
When I hear things like this, I wonder if I am hearing the whole story.
For example, if the vehicle in question has different sized rims (and tires) front to rear - AND - the listener has the opinion that tires can only be rotated front to rear - THEN - the listener comes to the conclusion that the rims need to stay in position and the tires get rotated.
I run into stuff like that all the time.
Exactly. I have an MR2 that requires the rims to stay on the same wheel, because it has directional tires and the rear tires are wider than the fronts. So the tire has to be removed from the rim and switched to the other side, or else the tire gets put on facing the wrong direction which sucks for grip and for tire longevity in general.
For a normal car, however, leave the tires on the rim and rotate as usual. The machined surfaces conforming to each other sounds good, but in practice that 80 lb/ft of torque you’re clamping the wheels down with is going to squash out any slight variance in the rotor/hub/wheel surface.
what make model auto? it may indeed depend on what type vehicle you are talking about.
even something mundane like a dodge viper has this issue.
CapriRacer, Shadowfax, and cappy all make a good point.
Perhaps if we knew the identity of the mystery vehicle, we would have a better idea of the validity of the advice. As was said, while the advice that was given is not valid for the vast majority of cars on the road, it is possible that the car in question does mandate non-rotation.
If you think a Viper is mundane, I’d love to know what you drive 
My V-6 Fiero Comes From The Factory With Different Sizes On Front And Rear. I Agree That This Is Correct Under Certain Conditions. We Do Need The Whole Story.
CSA
It’s a Mercedes wagon. Same rims all around. One tire size. Let me add that this is Germany, where kooky car ideas are if anything more rampant than in USA. My neighbor fills his tires with nitrogen.
Now that the OP has finally given us the needed details on vehicle type and tires, I will restate my original answer:
[i]I agree that this is very strange, as well as incorrect.
Apparently, these guys believe that they know more than the engineers who designed the car.[/i]
Tell your father-in-law to open the glove compartment, take out the Owner’s Manual, and read what the engineers at Mercedes-Benz had to say about the subject of tire rotation. I am fairly confident that the manual will illustrate the correct tire rotation pattern for the car. Then he can either take the car back to the original weirdo mechanic for tire rotation, or he can use this as an opportunity to find a new mechanic with more conventional ideas.
of course id LOVE to even drive a viper. that was my attempt at tongue in cheek humor!!
Yes, the German mechanics can be a PITA. and if your father in law does not “sprechen sie deutsches” fluently, he is subject to being taken advantage of during this stay in Germany.
Unfortunately my son is over there now, and has had to get a handle on the language to stop attempts like this from squeezing the wallet. It is done all the time!
Is the car staying over there, or are you bringing it back to the US? just curious where he lives?
My father in law was born in Germany and has never lived anywhere else. I’ve been here eight years. There are bad apples everywhere, but I have had better luck overall here than I did in the states. True though, you’ve got to speak the language, and that is particularly difficult with things automotive, since a lot of words won’t be in the dictionary. Can anyone guess which part translates directly as the “light engine”?
“light engine”: alternator?
Starter?
Wunderbar!
My neighbor fills his tires with nitrogen
So do I . . . Well I use 78% Nitrogen with 20% Oxygen 1% Argon and a mix of other gases. 
Not only is this a strange recommendation, it’s actually a bad one. Pulling good tires on and off rims can tear the bead up and lead to slow leaks. The suggestion unneccessarily stresses the beads.
Formula I drivers don’t have to worry about this. They change the whole wheel and tire together. And yes, their tires’ placement is predetermined and marked on the tire. But if I planned to go in excess of 200 mph bumper to bumper with other cars for 500 miles I’d want perfection also.
Pulling good tires on and off rims can tear the bead up… I was thinking the same thing. Again, probably not a real world problem, but a much more reasonable consideration than some mysterious harm coming from moving the rims around!
Formula I drivers don’t have to worry about this… I had no idea! Again though, probably not an issue with Opa’s bog standard Michelins, which probably never see 80mph.
This brings a question though. There are lots of people here who drive 150mph on the highway in their way-too-powerful BMW’s. As far as I know they don’t do anything beyond running 19" rims and wide, low profile tires. I wonder if there is any weird advice being marketed at this group?
There is. I’m confident in stating that the tire shops selling nitrogen probably tell them how superior it is for high speed driving. Most of the salemen telling them this probably don’t have a clue what the difference between “100%” (another fallacy) nitrogen and regular air are, but they’ve been told to sell the nitrogen.
My advice to them would be to slow down. Both the drivers AND the salesmen.