hello everyone. 
i’m not sure if you already talked about this here. in the latest version of glyphs (767) option(alt)-dragging a path-segment produces a new anchor, if you still (accidentially) have an anchor selected. you can duplicate curves this way too.
this wasn’t the case with glyphs1, which made massaging paths a very meditative job, without having to de-click selected anchors and not worry about duplicates.
In Glyphs 2, opt-dragging duplicates your selection.
You want to change the curvature of the curve by dragging the segment? Leave out the Option key.
Try the latest cutting edge version. There were one or two dragging bugs that have been fixed.
thanks. the option-key keeps my angles though, at least on segments between a green and a blue anchor.
after a few more glyphs-days i will get used to it i guess.
Oh, I see, I didn’t get what you were getting at at first. You are right, for what you intend to do, you must make sure, there is nothing selected.