That's one way to do it, although I typically er a bit toward the rich side of things vs right on the edge of being lean.
I don't have a saw in my line-up where you are going to be able to adjust it in the cut, so I'll start a cut and stop for each adjustment as I lean it up to find the ideal adjustment where the mixture is correct vs it hitting the rev-limiter.
I'd also clarify that when I saw "er a bit rich" I'm not talking where you are loosing any power in the cut and the saw is "puking" all over itself, not making optimum power, etc. I've just found over the years that being a little conservative is easier on the P/C and I've never once "smoked" on in any of my saws. Matter of fact my 480CD was purchased new in 1989, has at least a zillion hours on it, and P/C and compression are perfect..........Cliff