If you have never backed an osage bow in your life, Roy. You cant stand up and yell it's not needed. 
That makes no logical sense.
If you have backed Osage bows and they haven't broken... you 
can't say if they would have broken if left unbacked.
Conversely if you haven't backed any and they haven't broken... then you 
can say they didn't need backing.
The only scenario that suggests backing may have been necessary is if you have made unbacked ones... and they've broken! 

Sorry if that's all a bit pedantic 

Just sayin'
BTW I do have an interest as I have some thin ring Osage from the Monster tree 

 and I'm toying with how to handle it.... single ring back, rings running back to belly... or to back it?
Del