It doesn't actually matter what the secret letter says.
So, a Green Party MP wants a tram instead of a tunnel for cars. Not a big surprise.
The claims are that the MP cares so deeply about the tram that they threatened to quit unless they got it. Again, not a big surprise.
Which is what makes it all the more extraordinary that Julie Anne Genter refuses to release the secret letter.
Because, chances are, its contents will be a massive disappointment.
If the letter is what we expect, then its release will kill the story. We'll read it,