"read [ with a SC ]that it takes 14.7psi of boost to double the WHP "

CONSIDER that the 14.7 psi boost must be at the same non boosted temperature as each 11F in rise drops air density by 1%. Otherwise you need more boost .. say with 100F rise the entire power loss is 9% not just the added power from the boost so really an 18% loss which requires [3 more psi to make up for the temp rise which raises temp further so you really need 4 more psi or 18.7 psi [~~~+-]..........why you must have intercoolers.
ALSO you must factor in parasitic loss to drive supercharger [20-40 flywheel HP]. That requires say another 1-2 psi just to turn supercharger at high rpms.

Non intercooled supercharging is best when you only need 25-35% more power. less fussy.