Tyler, devitrification would not occur from cooling too quickly, in fact, cooling too quickly for the crystal structure to arrange is what causes glass to form. A "chill phase" would only cause more of a likelihood for crystal formation in certain situations (an example being crystalline glazes).
Annealing cycles for most soda-lime glasses begin around 900 degrees Fahrenheit. The rate of cooling used is dependent upon the thickness of glass, I could approximate, but would have to look over notes for definite answers. Thin and consistent glass will actually "self-anneal," or cool to room temperature without succumbing to material stress. The critical point at which the glass is most likely to crack during the annealing process is ~700 degrees Fahrenheit for common soda-lime glass... When Jawpot does the slow cool above 1840, I don't see it doing anything for the work (besides lending some good mojo). If he's still achieving successful results, the kiln is actually doing all the work in the annealing process.
In the case of interfacing glass and ceramic materials, (as mentioned) the coefficient of expansion (CoE) is a large determining factor of what will work and what won't. BUT at the end of the day, when we have the "crazing talk," there are a lot of potters who don't particularly mind crazing.
In the case of glass+ceramics, more glass in the situation is referred to as an inclusion (of the ceramic material) and the more abundant material (the glass) is more likely to fail. The ceramic material is more resilient, so when the ceramic material is in the greater amount, the glass will still fail (crazing), but the result is a lot more pleasant. Just food for thought...
On the note of the OP, just try everything out. Casual science doesn't always produce the best results, but it's always exciting and worthwhile. Don't feel as if you have to fire to c10, but don't feel as if you can't fire to c04 either. The glass will surely melt, so the maturity of the ceramic material should relate to this (meaning fire your body to maturity, so it looks as if it has some "melt" goin' on).
I think that's about it... Credentials available upon request!