Revise for Us!

I regret that these structural flaws prevent us from making an offer on [Title]. However, if you are willing to revise the manuscript, we would be interested in taking another look at it.

It's always tricky to know when to revise for someone. These people don't even tell you what they want, so that's either good or bad.  Not sure which is better.  The question is always whether or not to go down this path.  It's hard to remain confident after getting a note like this, but I always send it out to many places before taking it back and thinking long and hard about what to do next.  Sometimes, a revision is called for.  Other times you stick to your guns.