Well in the fiction in the main book, Sava's muse doesn't come online until a short period of time after he wakes up in his new body, so an inactive copy is maybe sent along with the ego.

That just seems like a really bad idea to me. :/ The whole point of the stack is to be a safe copy of the pure ego, AFAIK. What's so hard about making separate backups a simple little muse?

I'm with Yerameyahu, here. I could certainly see a copy of the muse being stored along with the ego when you make your backup. I could also see people making regular backups of their muse between backups of their ego, either to a secure storage site on the mesh or to an off-mesh physical storage medium for the particularly security conscious. All too easy to make permanent loss of your muse a rare event without putting the ego at any greater risk.

When you backup yourself it is only natural to include your digital possessions. Your ego might be most important, but keeping your contracts, signatures, encryption keys, personal files, blueprints and muse are pretty high priority too. It would be odd if backup insurance doesn't include that. There might be adventure hooks there. A PC restored from backup discovers unexpected "gifts" among their files, almost as if the backup service had accidentally included somebody elses files - which sounds exceedingly unlikely. But maybe they *are* that other unknown person, and for some reason has erased their memory and identity? Or was it somebody else? Is the files a present from Firewall... or a dangerous trap arranged by a very powerful group with access to the backup service. But why?

Don't worry, you were pretty clear. I've been reading these last several posts as support for your argument as to why the muse doesn't _need_ to be in the stack or part of the ego.