Why dual-grip Strength matters
Standard two-handing boosts effective STR by 50%, rounded down for this calculation. For instance, 16 STR meets a 24 STR weapon requirement. DEX, INT, FAI and ARC never gain the same boost.
The game publisher's Advanced Stats guide confirms the standard 1.5× Strength rule and its 24/16 example. Certain paired and special weapon behaviors are exceptions; disable the boost where appropriate.