Can I wash my yeast from a IIPA with a og of 1.079? 9% abv?
Yes. It will make beer.
Some folks caution against it because high gravity can leave the yeast stressed.
I've used yeast from high gravity beers before with no issues. I make a point to only use it once if it is from a beer with an OG above 1.070.
Local brewery around me "flydog". Will harvest up to 8-9 generations off their "ragin bitch" which is 8.2%. There lower abv beers they will use 10-12 generations of yeast