My Little Pony: Friendship is Mafia

[Solid Snake]

There's a lot of reasons to dislike Sifright's plan that IHMN has not accounted for. (

The 'doctor' or 'protective' role could be lynched D1.
The 'investigator' could be lynched D1.
The 'doctor' or 'protective' role could die N1.
The 'investigator' could die N1.
The 'doctor' or protective' role could be lynched D2.
Mafia could simply target Sifright to be killed N1, effectively guaranteeing that Town wastes an investigation, all the while encouraging us to investigate Sifright, knowing that Sifright would be killed.
Mafia could have a 'watcher' role (they do exist), either one-time or permanently. Mafia 'watches' Sifright and can view anyone who visits him. Presto! The Mafia knows who the Investigator is.
Either the Doctor or the Investigator could be kidnapped or killed in a manner that leaves no trace (Mafia has this role sometimes, too! They did in my game!) Then Scum can claim the Investigator (if he's kidnapped.) Or Scum can pretend the Doctor's still out there, knowing that he isn't and can't save anyone.
Sifright could be a 'Godfather,' in which case as Scum he'd scan innocent even if he is not innocent. Every 'investigator' has limits to his power(s). Actually, it'd be to Sifright's advantage as scum Godfather to make the investigator waste a scan 'confirming' him.
Sifright could be SK or Cult; in some games, SKs or Cult members scan innocent by Cops.

...Really there are so many ways this could backfire.
General Rule: As investigator you NEVER LET YOURSELF BE TOLD WHO TO INVESTIGATE. You trust no one, do your own research, and don't reveal your role and your findings until you have to.

HOS: IHMN for being stupid.