I viewed the video demonstration for Planswift and in the video they create a curved linear takeoff by clicking on 3 points on an arc while in the middle of a continous mode takeoff of several straight segments and then continue with more straight segments. Then they do an area takeoff and create a curved segment of the perimeter the same way.
What they don't show is how they switch from the takeoff becoming 2 straight segments with the 3 points to 1 curved segment. They don't finish and come back and adjust the straight segments to curved like OST would do in a typical continous mode linear takeoff. Is there a special key to press during the takeoff to tell the program that the next 2 points define an arc from the previous point instead of 2 more straight segments? Not that this is a critical point, but it's shown as simple and quick in the video and that might be deceiving and it's actually slow and difficult in real life and by the end of the day you are ready to pitch it all out the Window. (Pun intended.)
What if your 3 points don't match the arc exactly, can you adjust after finishing the takeoff? Moving, adding and combining perimeter end points in an area takeoff makes OST very flexible and I use it a lot on purpose to rough out an irregular area and the come back and perfect it. It makes it quicker in the long run.