Surely the simplest solution would be to have two classes of longbow. One for ELBs and one for R/DLBs. I'm not sure how the BLBS purists would take it but it would stop the 'cheating' claims.
Hmm...actually on second thoughts maybe it wouldn't stop the 'cheating' claims. Recurve archers seem to always be complaining about 'cheating' compound archers, and longbow archers seem to brand everyone else 'cheaters'.
All in jest of course...
