no they are not, anything below 7 is good for downstream and anything above 33 is good for upstream. I would only be worried about the upstream power if he lived a million miles away from the cab.
If you want to settle the arguement (op) buy one of these and we'll see if it makes any difference:
http://www.ebay.co.uk/itm/forward-pa...item2a2061a632
edit: I have just remembered that the shub can only tollerate something like a total of 33db across all the channels it is using otherwise it dies. While each channel is within spec cumulatively they are too high so I defo recommend buying that attentuator to see if it helps. Apologies to sollp, you was right in a round about way.