3rd tank convinced me. The gunk was from Saline.
Some of my flavors react to the saline differently though.
Blackberry stays pretty damn clean but I just scraped crud & refilled my strawberry milkshake and it was pretty nasty.
I chose my Kool Berries to experiment with because
1. It's my favorite so I know it best and
2. It's usually pretty gunky
3rd tank could have been refilled without cleaning.
Thanks for the suggestion
@Letitia
I'll remake my next in line with DW to extend this test but I'm confident I'm done with saline. Bummer is I have over a half liter of about 6 different flavors already made. I'll just add a few drops per tank into the new stuff but I think I'll stay crud-free from now on.
Now for the on topic content - I just chain-hit my DW vape 4x exhaling through my nose. It got moist but no dribbles. If it was saline it would be flowing copiously.
win win win