I saved my iOS 5 SHSH with TinyUmbrella, and now I have 4.1 SHSH too?
Here's a helpful guide on using TinyUmbrella, SHSH blobs, and downgrading. Depending on your hardware, downgrading may or may not be possible. I haven't tried downgrading anything since iOS 5 beta on original iPad and iPhone 4. It worked in both cases, but I'm not sure what you have. 

The version of iTunes may also play a role in your ability to downgrade. For instance, the latest iTunes may not allow you to restore a version of iOS prior to 5.

Sorry if this wasn't as solid an answer you were searching for. Maybe it'll give you a starting point to experiment, if you have the time though.