I've seen it suggested that V can leave a possessed body (becoming a disembodied spirit) but not his own. I don't recall seeing anything (either in canon or in HPMOR) that confirms or refutes that.
I share your concerns about #2, although generally "once you have physical access to the hardware, it's over" -- if you can catch Voldemort or Dumbledore or whoever asleep, you can smash their head with a big rock or something.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 114, and also, as a special case due to the exceptionally close posting times, chapter 115.
There is a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)