I have experimented with this a lot. I used to do it all the time, but have now found that shifting into neutral is unnecessary. If you back off the gas and max out the instant FE display, but keep on enough gas to stop the regen from engaging, then you're coasting as freely as you would in N. There's no regen and no engine braking, it's just like coasting along in a normal automatic.

If you do use N, DO match the rpm before re-engaging, it does work and it is better than slamming it in. If you don't rev-match, it probably won't do a lot of damage but it puts more wear on the tranny. You can't always anticipate what rpm the cvt will shoot for when you return to gear, so I just rev it to about 3k and let it take up the diff. This is a lot smoother than dumping it into gear from idle.

My technique to make sure I didn't forget to switch back to D was to never remove my hand from the shifter until I had shifted back.