This is true, though I’ve even lost track of split single-sig in the past! Honestly, you have to regularly revisit these things (yearly, at least) to keep the neural pathways fresh.

Toying with single phrase backup with a simple translation or one-step change stored only in our brains. That way you could just hang the thing openly on the wall in complete security. There’s risk however you cut it really, mitigations down to personal preference and capability.