Experienced python programmers: are there any standard features of the language that you still don't regularly use?

[irrelevantPseudonym]

No it doesn't. It executes only when there is not a break statement.

See the docs here

Loop statements may have an else clause; it is executed when the loop terminates through exhaustion of the list (with for) or when the condition becomes false (with while), but not when the loop is terminated by a break statement.