[Formulajones]

One reason your reading that might be because cams rely on splash oil and they think those roller bearings need it.

It's also another reason you'll read some people like to idle their engines higher, like 1000 rpm or more so it gets more splash oil.

But if you buy good rollers with pin oiling it's a moot point also on flat tappets when you get good lifters with EDM oiling directly on the lobes or the lube option hydraulics, again it kinda makes all that pointless.