I know UA/AA/DL all have fairly specific guidelines for what kind of meals get served based on specific flight mileage and distance along with a list of "exception" flights...all of this is clearly posted on their respective websites and although AS includes flight length guidelines for Y meals, there is nothing listed for meals in First class. I have to assume that they must go by some sort of guideline and just choose for whatever reason not to make it public, correct?

It's tough to try and guess when you have flights that offer two very different types of meal service despite being almost the same exact mileage and time of day....for example DTW-SEA leaves around 5pmish and is around 1900 miles....it gets "dinner" (the full 3 course transcon service) while PVR-PDX leaves around 5pmish and is also around 1900 miles and it gets a "snack" (probably a sandwich for a 4+ hour flight smack in the middle of dinner time)....maybe DTW-SEA is an "exception" flight (if indeed AS has something like that).