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At the end of the day, people have the option to exclude these moves from their movepool submissions. Neither are particularly unhealthy for this concept, so I see no reason to disallow them.
While I don't like either of those at the moment, I think letting the moveepool submitters decide on it is a better choice than deciding their inclusion via poll. So I voted to let them the maximum degree of freedom in their submissions.
I could care less about Ice Fang, but U-turn's job can be accomplished with various non-attacking moves without breaking Heatran's balloon and screwing it over with Dugtrio.