I heard something interesting from a fairly reliable source.
When a black and red wire are next to each other in a panel, they should be tied together at all times. Why would this be?
I inspected a house today with excessive amounts of red and black wires neighboring each other.
It’s to ensure the red wire doesn’t try and run off with that trampy little neutral wire from down the panel. You know, the one with all the mini-skirts and the midriff baring tops.
Perhaps what your reliable source was referring to is if you have a red and black from the same cable it is usually good to have them on the same 2 pole breaker. (one on each side) since this is probably a 240 v or multiwire 120v circuit
The 2008 NEC article posted does not apply to the postersd question, their is no issue of the " Red and Black" being a ungrounded and grounded pairing in this question by the original poster.
Now I agree totally with the concept of210.4(D) and its revision or addition as it will simply attempt to make the use of a multiwire circuit safer but alas the “Reliable” source was incorrect.