Those are very general outlines on boost vs static compression, what is most critical is Dynamic compression which is impacted by both static and cam timing, particularly your intake closing event. Also the use of aluminum cylinder heads allows better heat dissipation as well and carefully considered effort towards your fuel and ignition timing can allow you to make more boost safer and more efficiently. Those 'rule of thumb' charts I suspect are designed to deter people from going too wild with their selectoons knowing most are going to simply bolt a blower on their existing engine, not for those carefully selection parts for a purpose built 'blower motor' like you and I would be building.