Degreeing a Cam, or not.....

There is probably some truth to this, but on the other hand, there are times when you might deliberately want to install the cam with different amounts of advance (using an offset key). The only way to do this is by degreeing. Some people seem to just want the lopey idle and don't care about performance, for example...

I had the heads off and was installing a new timing set, so I thought I would check my cam, and as it turned out it was right on spec. But I didn't know that until I degreed it.

I read somewhere that if you use the timing set that is the same as the manufacturer of the cam, it will be close OOTB. This may be an old wives tale, but is there any truth to this? (experts)
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