Driveshaft orientation

[gideon]

I recall watching an episode of Wheeler Dealers where Ed China made a point of reinstalling the driveshafts the same way round that they came out.  The justification given was that switching the direction in which they were loaded could cause metal fatigue.

I'm about to strip and paint a pair of driveshafts and I'm wondering if this is a real concern.  And if so, what is the best way of marking the driveshafts so that I can be sure I'll never get them muddled up?

[TurboFource]

I marked mine with small punch marks starting on the drivers side and to keep the relationship of the parts the same 1, 2, 3 and 4 marks, so there were two 1s and so on

[jbcollier]

If a half-shaft or drive shaft assembly has been balanced, it is important to mark everything so you can keep it in balance.  Otherwise, it doesn't matter.