I agree with Big Jim, and the Bow Bolt was my little invention.
John makes one of the best bows out there and he will and does use the bow bolt but he won't retrofit one. As Big Jim mentioned, 45# is the limit without having had the bow made to accept the Bow Bolt in the first place and I agree. If the bow is being made with the bow bolt in mind, then the sky is the limit if it is reenforced properly. I know Gregg Coffee is making some "dangerous game" bows in the 80# + range with the Bow Bolt without issue and I belive Alan can attest to this.
Keep the Griffin as it is and if you want a 2 piece, have it made during new construction.
Craig