Can't say I've ever seen music noted like this...

Usually, you only have to learn it for one piece and never see it again.

 

Really depends on the shows you're playing and how much new music is on the programs. There's definitely some very piece or composer-specific techniques/notations out there, but in a more progressive ensemble that gets a new piece or two on every program alongside the standard rep (or on entirely new music sets), you'll definitely encounter overpressure/scratch tones fairly often

 

We used to call a hot-off-the-press piece programmed between two old European masterpieces a s**t sandwich!!

 

I see these type of crush tone markings on a regulr basis.
weird and ugly at first. I am sure people thought the same about col legno,bartok pizz and sul ponticello as well once. Not to mention quarter tones.
Music is evolving whether we like it or not