I’m familiar with this behavior for alt+click rather than double click.
I did a check of different plugins from different manufacturers to see which behavior is the prevalent one which users will probably be most familiar with.
Supporting alt+click and not double-click (some also support cmd+click):
Slate, Brainworx, Waves, Sound Radix, Apple
Supporting alt+click and double click:
Supporting cmd+click only (no alt+click):
Supporting double click only:
It would be nice for alt+click to also do what double click does (for now I’m subclassing Slider for this).