Why is Storyville Being Singled Out?

It is important to note the highly disproportionate nature of the cuts
threatening Storyville when the BBC needs only a 3% cut overall. We don't
know why Storyville is being singled out, but it is clear that the threat comes
from the Channel Controllers who are under pressure to make cuts in their
budgets.

We do know that Mark Thompson, the BBC's Director General, has repeatedly
stated his support for creative long-form documentaries on the BBC in general
and for Storyville in particular, although he is on record stating that keeping its
budget tight is 'healthy' for the producers involved.

Why is Storyville Important?