How to best edit a MC clip can be confusing. It exists in three possible forms: (1) The MC clip in the Event Browser, (2) The opened MC clip in its own "timeline", and (3) The MC clip added to a project timeline.
In general I recommend using the MC clip in the Event Browser, enabling the Angle Viewer CMD+7, then skim the MC clip and mark favorites, rejects and keywords ranges. When that is done, set the Browser filter for "Hide Rejects", make a project, query the Event Browser and add favorite or keyworded ranges from the MC clip to the timeline. This is the same "FCPX-style" workflow as for single-cam clips.
You can add the entire MC clip to the timeline and start cutting it up -- just like you can dump all your single-cam clips on the timeline and start manipulating it. However that is not necessarily the optimal way.
Note there is a UI bug whereby the skimmer may not activate on MC clips in the Browser unless you briefly skim another clip first.