I thought I replied to this one, but apparently not; I was reminded of this by 'Make reviews great again! 
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As far as I know, there’s nothing that does what you’re asking—at least, I’ve looked for it previously and not found it. i.e. I don’t think there’s any keyboard shortcuts to jump between commented moves. The analysis tree does indicate commented moves with a blue circle, but personally I don’t find them very easy to distinguish from non-commented moves.
BenKyo commented once that at some stage in your Go development, you need to look at individual moves, so yes, I understand, tap-tap-tappity-tap through every move. I can’t help feeling though that it’s easy to miss the “broad strokes view”, remind me of the key choice point moves (which are usually going to be commented moves).
Just a thread nudge, yinno, in case the developers run out of things to do 