[vict7]

I feel this is similar to how my brain works. If I am not using a skill close to every day/week then it can atrophy fairly quickly. On the plus side, it also comes back quickly (usually) if I start using it with greater regularity again.

I notice that general concepts usually stick better in my brain than specific things like your example with ‘when’. Even those are pruned down a bit after long enough though.