Can't say that I've ever came across "static loaded diameter" before. Either way, there's a difference between a tire's radius and its static loaded radius. Its radius is not half of a "static loaded diameter".
And you're right. It's very simple to leave any official numbers out of it completely and just use a tape measure to find out what might fit. Not sure why that is such an unpopular method. Other than that it requires thinking.
Although, it can be tricky to determine exactly how much a bump stop will deflect, even on a live axle.
On the other hand, articulation plays a smaller role with IFS.