I have a new 2023 2500. There are a couple other threads about this, but none that are helpful, and the manual only touches on how to use it, not when to use it. Is the ERS selector on the steering wheel to aid in towing? I can imagine it being helpful in a situation where you're towing uphill and struggling a bit with the load and the transmission wants to keep shifting up and down repeatedly. If you activate ERS and tell it to not shift above, say, 3rd gear you could limit the shifting. Other than that, I don't see a use for it.