There's also no reason not to change it if it makes things faster. Have you ever noticed that in my mod, brush drawing produces no lag, but in tpt, it's a laggy mess? Especially at large sizes, which had to be disabled because of it. That's because I actually did my own fast circle algorithm. There's one for full circles, and another for circle edges, because when doing lines you only need to do the edges.

I don't think lines are particularly slow, not like circles are. But it wouldn't hurt to change this.