One thing I notice in the manual is in reference to strength of schedule, it doesn't refer to a specific computer program or ranking. I cannot remember if I have read before whether the committee commits to a specific system.
Looking at the term generally, though, I think it can be a bit more subjective. Just as a thought experiment, let's look at Furman an Montana.
What we know, objectively, is Furman played an all Division 1 scholarship schedule. We know Montana did not. Let's compare strength of out of conference schedule first.
Butler
@ Utah Tech
Ferris State (D2)
Ferris State is a good D2 program, but still a D2 program. Montana struggled with them. Butler is a non scholarship Pioneer league team. Utah Tech is a new school to the FCS, but currently 2-8.
When you compare that to Furman playing South Carolina, Kennesaw State, and Tennessee Tech, I think it's a clear advantage to Furman on strength of out of conference schedule.
On in conference schedule:
This is where everything just gets really subjective, in my estimation. They are virtually no common opponents, so you have no 1:1 comparisons to make any sort of evaluation.
As I see it, both Montana and Furman played a winless team in their conference - Northern Colorado and the Citadel.
Beyond that, Montana has some wins over a decent UC Davis team and a middling Idaho State. Again, this could be akin to beating Samford and, say, ETSU. We have no way of knowing whether Samford would beat UC Davis, but they both hung around in the rankings for a bit and will likely sit on the outside of the playoff field.
Notably, Montana lost to Northern Arizona. I think this may be akin to Furman losing to VMI or something. UNA is "ok," but far from "good." Again, is VMI better than UNA? Who knows?
Montana also beat Portland State. If there's one clear difference in the schedules, it is probably that Furman will have to go through two "bad" SoCon teams (likely 0-11 Citadel and likely 1-10 Wofford) while Montana arguably played one more "meh" program like Portland State.
But then you get to the big games. Montana beat Sacramento State, Idaho, and plays Montana State this weekend.
While I realize that those three teams are technically ranked higher than Furman's wins over Mercer, UTC, and WCU, can anyone objectively say that they are better teams?
I guess this is what I keep coming back to. Yes, Idaho is higher ranked than Western Carolina, but to call Idaho a better team is just a guess. There's no objective basis for doing so.
That's why I am suspect of computer rankings. Computers don't watch the games. Even if they did, you can't draw many conclusions when the two teams don't play the same opponents.
Maybe Montana State or Sacramento State would blow the doors off Mercer and UTC. To say that, though, is just a guess. We have no idea.