Mastered as in I could teach it to others, and assemble many complicated rules for many complicated patterns.

I am always impressed with folks that retain it.

I would a ton of it for a month or two, and then do nothing with it again for more than a year or more.

It takes a lot for permanent burn-in for me. That’s the curse. The blessing is that I learn very quickly.

Waterfall: Spend 10 years compiling written functional and technical requirements. Cancel the program due to budget overrun.

Finite rules for perfectly sifting infinite options

I mastered and forgot almost entirely RegEx several times now

Closed in the winter, Open most of the summer so that the whole house fan can pull air in and through the bedroom cooling things down.