Retain 50% on Miller and replace Dermott with a 2nd

i'd do that

Leafs don't have the cap for Miller...even with retention. Why do we see so many Leaf trades trading Dmen? Leafs only have seven NHL competent Dmen. They can't trade one without getting one in return (and then what would be the point)

I think you are seeing posts like that because NHL insiders have basically confirmed the Leafs are shopping Holl and Dermott

NHL insiders? Reporters that start rumours, so people think they are "insiders". Oh I don't object to Holl and Dermot being traded (or any Leaf) but as I said, unless the Leafs get an NHL Dman in return, Holl and Dermot won't/can't be traded.
For some reason on CapFriendly, there is belief that virtually all Leaf Dmen are poor, and other teams bottom enders are so much more superior.

Speculation is not confirmation of anything.

Yup, they are the worst defensive team in the league despite being top 10 in Goals Against. Their PK sucks despite being top 5 and their goalie is a backup despite being a current Vezina contender. Why? Mob think

Good morning, PBMNFMOWG. You and me seem to think alike regarding structure of team.

Long time hockey reporter Al Strachan was fired from Hockey Night in Canada when he professed being an insider at what was said at the NHL governors meeting. When he couldn't back up his claims of hearing first hand what was said....he was axed. These reporters are largely entertainers, trying to outdo one another. I encourage all fans just to watch the games, and they will be as smart as most of these reporters.

Dude, TSN has said that is what they are doing. Does not mean it will happen but they definitley looked into it before some injuries happened.
They do talk to people around the league and within the team more than you would.

Leafs also have Beiga and Menell that have played NHL games vbefore so they do have a 7th D man that could fill in.

If Miller were to go to the Leafs, retention and Ritchie would make the Cap hit work. There is no Canuck D the Leafs would want that they can afford under the cap.....trust me on that. While Miller would be a nice fit another solid D will probably be where they spend time/assets/cap space upgrading. Just my opinion.