Depends on the artwork being framed if its of any great value or inportance then yep conservation matters
but at the end of the day if your customer wants the work framed and no one will do it then this method is an alternative at least the work is protected. We are not talking about victorian pine panels here, woods like obeche are not as hazardous, the wood would not be exposed to the elements once wrapped in a good quality archival paper (available in rolls)
and a archival barrier added to the back
If you want to go down the conservation road
what about the glazing?
sealing the frame from atmospheric conditions ?
central heating?
where is the customer going to hang the framed work, (above a radiator?)