PhD physicist here. Struggled through the 'normal' public education math program, and didn't get good traction on stuff until college when my instructors starting focusing on more 'evidence based' math and physics.

Also I never completely learned my multiplication tables to the point where they were reflexive, such was my loathing for rote memorization. To this day I sometimes need to pause to mentally crunch something. This sucks for small numbers but it means I have the mental tools to grind out bigger ones that other people would need calculators for.