Pete Rose is a great example of that. He started out as a middle infielder, and then moved to the outfield, mostly corner outfield, for 6 years. Totally lost his third base skills. He had to fake it for many years after they moved him to third base. Everyone that saw him there marvelled at how he could play third base after losing all his skills.
Must have just been faking it.
Dave- Let us take a stab at accuracy. The "everyone" folks who "marvelled at how he could play third base" were either drinking buddies of Rose or folks with a vested interest in keeping Rose happy.
Rose was a very poor defensive 3B when he played there from 1975 to 1978. Moving him there was a move entirely based on offense. As one example, just look at Baseball Reference defensive runs saved for that period. Rose was 33 runs below average cumulatively those four years---one of the worst 3B numbers in the majors at that time. Rose himself acknowledged in retirement that he wasn't the greatest 3B--which for him is saying something. Best thing he could say was that he worked very hard there, which I'm sure is true.
And, there is the historical context why he was playing 3B in the first place, which is interesting. What happened was that Reds had to figure out a way of getting George Foster's bat in the lineup everyday. Rose had been in LF--where he belonged. But, Foster was turning into a monster bat and could only play LF. Playing 1B was future Hall-of-Famer Tony Perez. RF was Griffey. So, the only choices for Reds were either to turn Rose into a part-timer (!!), trade him (!!!), or put him at 3B. That's why Rose played 3B in the first place. It was the ONLY practical option.
So, what you are alleging as everybody thought he was wonderful at 3B is hogwash. Naturally, Sparky had to pat Rose on the back about how terrific he was playing--this is PETE ROSE we're talking about-- but any objective analyst knew he was poor defensively. He was a LFer or a 1B de facto at that time of his career. When he finally left Reds, he played 1B in Philly (badly).
Finally, aside from the inaccuracy of your post, it is always interesting that whenever anybody tries to come up with (alleged) examples contrary to defensive spectrum notions, it typically is a Hall of Famer rather than a mere mortal. By definition, HOFers tend to have very atypical gifts. They are outliers. So, even if Rose was a contra example--which he is NOT--it would be the example of an outlier. Put another way, it just proves the point if only outliers are the (alleged) examples.
In any case, you just gave an example of exactly why the spectrum principles are sound.