Roy makes a fine d/r all the time
Maybe the low gpp problems are a glass specific thing. Since making bows I have not had one laminated bow fail in the gluelines. I'd say a good wooden bow (self or laminated) easy takes 5gpp without problems. The other question is weather its a comfy shooting. I would say glueing wood to wood makes a totally uncritical bond whereas glueing glass must be very tricky compared to. However using wood for bows is critical per se out of other reasons - we struggle with failures in compression and somtimes tension.... jm2c
You may be right about the wood bows being more forgiving on low gpp arrow weights. I don't build all wood bows very often.
The issues that come into play using glass or carbon backing is the dramatic difference in compression differences between the composite and wood. You rarely have issues on the back of the limb under tension, but the belly side is a different story.
What type of wood laminations used under carbon on the belly side of the bow makes a huge difference. The carbon doesnt compress at all, and typically buckles and shears the bond between wood and carbon in limbs with shorter working limb length. It's a must having a hard maple belly lam that has good compression ratings to hold up. But even then....Carbon on the belly side of a recurve or R/D hybrid long bow is dicey. Glass on the other hand is more forgiving in compression, and much more durable than an all wood bow. Just the fact that humidity levels , and MC levels on glass bows are not an issue, and can be left strung up for long periods of time with very little, if any string follow or poundage loss has made the use of glass so popular. Longevity is far superior too.
But i admire you guys building bows from just wood. It's an art form in itself. Kirk