Fixing timing on an acoustic guitar track: nudging, crossfades, warp, etc.

Just finished watching the Eric Valentine video on crossfades, and am not sure how to accomplish a certain edit.

Let's say I have an acoustic guitar part, where one chord is a bit early or late, so I want to nudge it over?

How do I do this, without affecting the timing of the rest of the track, or having silence in the area where I "cut" the section and slide it over?

In the EV video it seemed he was doing this with nudging. I've also seen a video where someone used elastic audio, and warping to move a chord to the proper place, and then extend the tail over to the next chord so there's no silence...though EV didn't mention that method.

Any insight into the best approach here? I have a few chords I need to. shift around on a performance and want to do this with as few artifacts and as efficiently as possible.

Also, when crossfading acoustic guitar, is it best to use equal power like Eric suggests on piano, due to the more complex nature of a guitar chord (multiple notes ringing out and overtones? Or is equal gain best here?