I'd say that from the radio mfg's point of view, it's actual user problems with poor installations they've encountered, and best installation cures.

Take the following scenerios to get your mind in gear on how to view all of this;

1) You have 5 elements that might cause troubles, 4 are done correctly, 1 is done completely wrong.
Easily you know which was the problem and which to fix.

2) You have 5 elements that might cause troubles, 3 are ify, 2 are are done correctly. Now you have a mystery.
JR/Futaba/Spektrum/Hitec have had tons more experience than us and don't like such customer support issues,
soooooo they come up with their best recommended solutions.

The new 2.4 radios are somewhat more resistant to inteference issues, but NONE are 100%

So follow the radio mfg's best practices/recommendations and enjoy the warm fuzzy feeling of a job well done!
Do otherwise, and you're on your own as to the results you get. Sometimes the best recommendations just
can't/won't be followed (no room, etc).

Some are very lucky doing things ify, some aren't. What value do you place on your model(s)?
Try your best to follow the radio mfg's best practices/recommendations, then all we need do is improve our flying skills!