Half-full or half-empty in this case? For end-grain I find estimates of 75% stength on average expecting considerable variation joint-to-joint, assuming proper

Half-full or half-empty in this case? For end-grain I find estimates of 75% stength on average expecting considerable variation joint-to-joint, assuming proper pilot holes have been drilled. If the hold scales with the diameter of the screw, then a larger screw might compensate. The square of the wood's specific gravity might dominate differences: https://www.engineeringtoolbox.com/wood-screws-allowable-withdrawal-load-d_1815.html https://www.engineeringtoolbox.com/wood-screws-allowable-wit... Also, what is the pull-resistance on the snap joints themselves?