Snapping chalk lines on a log and using hand saws to saw down the chalk lines

Logs are uneven and there are a few things I do to help make the layout chalk line more accurate. I have also read a couple of tips like holding the line down in the middle then snapping twice and using braided spider wire fishing line. I also do this: I hold a combination square with a level bubble while the log is on my work bench on the ends and pencil in a line on each end where I want to start a saw line.

Then, I saw a kerf line on each end deep enough to hold the string (1/8th of an inch). I then tack in a nail on each end of the log in the middle of the kerf and in the middle of each end of the log. I then can attach the string making sure it stays in the kerf on one end and move to the other end of the log and keeping the string taut place it in the other kerf. Wrap the string around the other nail to snap. The same nail placement and kerfs can be used to snap a line on the other side of the log after turning the log over on the bench to snap a reverse line.

From now on I plan to use the mid point method of holding the line and snapping twice or on each side of any uneven knots. I use a moxon vise to attach the log standing vertical to the bench and web-strap the bottom of the log to two legs to prevent wracking. I saw kerf lines down the chalk line on each side at an angle with a handsaw and use a frame saw on each side of the log to keep the saw on track to remove the wood between saw kerfs. Does anybody else have any other tips?