Hi @rafberger , I posted a list here: Elements of Style - #5 by Thomas
I typically don’t change gears in ERG mode and just change my cadence.
But there are reasons to change gears in ERG Mode because of the momentum saved in the flywheel or force needed to speed it up:
If it is a climbing or technique specific training like you asked I change into a lower gear so it is less forgiving and closer to climing in the real world. You can’t really coast uphill.
If it has sprints or surges I change into a higher gear so I have more resistance, ERG has more time to respond better and I don’t spin out that fast.