A 52" stiff-handled and recurved wood bow without backing will have a high probability of breaking if drawn to 28".
And yet in the TBB there's a photo of a 48" hickory recurve stiff handled unbacked pulling 28".

. ...but gordon is correct in saying "high probability of breaking".
See...now your really confused ...I just built a 50.5" selfbow that I know could be pulled to 28" easy...I wood just incur a lil more set. Research,read,research,read...repeat