If it's not a warranted situation, the song doesn't work. Depending on how not last-ditch it is, it could simply fizzle, or it could backfire. In some ways, it's akin to using "Twist of Fate" - you're asking the gods to give you something extraordinary, and it's up to them to decide if you're worthy and what it's gonna cost you.
As a starting point, I'd put the following restriction on when it's likely to work: If there's not a decent chance Doug, his compatriots, and/or those he's protecting are going to die when Doug starts the song, it won't work. Plus, the more Doug is willing to die to succeed, the greater the chance that it will succeed. If he's not willing to sacrifice himself to win, he's not gonna win. Not that it means he has to die to win, just that he has to be willing to do so...
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Drunkard's Walk Forum Moderator and Prereader At Large
As a starting point, I'd put the following restriction on when it's likely to work: If there's not a decent chance Doug, his compatriots, and/or those he's protecting are going to die when Doug starts the song, it won't work. Plus, the more Doug is willing to die to succeed, the greater the chance that it will succeed. If he's not willing to sacrifice himself to win, he's not gonna win. Not that it means he has to die to win, just that he has to be willing to do so...
Offsides
Drunkard's Walk Forum Moderator and Prereader At Large