It occurred to me that there seems to be two (or more) schools of thought on how to label instrumentation in terms of numbers. P.Davydov says "I tend to use "Piano (solo)", "Piano (4 hands)", "Piano (left hand)" in the instrumentation field, just to be absolutely clear." I agree with him on those cases, but he seemed to disagree with using "1 piano" "1 violin" just to be clear.
Personally I prefer to put a number in front of the instrument to be clear (e.g. "1 piano"). That way it can apply to all instruments.
Is there something written on this (I'm sure there must be, but I haven't found it)? If there isn't, we should all agree on something so we aren't changing each other's edits

, which is what I've noticed we've done. KGill tends to agree with me (e.g. 1 piano, etc), I think.
I just feel that we all do things differently when it comes to this (based on my observations).
Thanks,
BKhon