Convert multiple line segments into curve segments

I’d love the ability to convert multiple line segments into curve segments. My habit is to put down all nodes at once first. So for example in a glyph like S , there is a lot of Option-Clicking to do. Is this a feature that exists somewhere?

That is currently not possible. And there will always be segments (except in an “o”) that doesn’t need curves. So I wonder what is more efficient: Adding all needed segments one by one or converting all and removing the unneeded ones.

There a script which does that.
Will post once I get to my laptop.

#MenuTitle: Curve All Straights
# -*- coding: utf-8 -*-
__doc__="""
Turn corners into smooths (useful when tracing)
"""
import GlyphsApp
from Foundation import NSPoint

def lerp(t, a, b):
	return NSPoint(int((1-t)*a.x + t*b.x), int((1-t)*a.y + t*b.y))

Layer = Glyphs.font.selectedLayers[0]
testSelection = len(Layer.selection) > 0

for p in Layer.paths:
	if p.closed:
		start = -1
	else:
		start = 0
	for idx in range(len(p.nodes) - 1, start, -1):
		node = p.nodes[idx]
		if testSelection and not node.selected:
			continue
		if node.type == LINE:
			prevNode = p.nodes[idx - 1]
			off1 = GSNode(lerp(0.33, prevNode.position, node.position), OFFCURVE)
			off2 = GSNode(lerp(0.66, prevNode.position, node.position), OFFCURVE)
			p.nodes.insert(idx, off2)
			p.nodes.insert(idx, off1)
			node.type = CURVE
			# node.connection = GSSMOOTH

hope this code is helpful.