I found this post here:"Paradoxically, aperture pours (pot melts) and high fire slabs, which are often fired above 1600F and held there for long periods of time, usually resist devitrification. This is because the glass is continuously moving, flowing, and presenting new surfaces during the period of time the temperature is very high."
I'm thinking that the artist above is making larger pot melts or has a better kiln schedule!
So I discovered so far that it doesn't matter what type of glass I'm using, I always end up with devitrification. I changed my kiln schedule so that I would quickly heat up the kiln to a slightly higher temperature than my original kiln schedule, that way I wouldn't have to hold it there as long, yet I still ended up with devit. So right now the only solution I know of is to use a lap sander on my pieces, or sandblast the devitrification off.
I am planning on manually venting my kiln down to the annealing temperature next go around to see if it makes a difference.
If anyone has any suggestions, please comment below! Thanks