Actually, Woodman, I'm sorry to say that for me terraforming facilities are generally useless. The planet regenerates by itself, slower, of course. Your example is a good one, but such cases are very rare. Disasters by themselves are quite rare. If bombardment was used more frequently, or if ground combat would be remade to damage the planet a little, maybe then the TF would see much use.
"Only an idiot fights a war on two fronts. Only the heir to the throne of the Kingdom of Idiots would fight a war on twelve fronts," - Londo Mollari