Robert_Charlton - 8:23 am on Apr 23, 2013 (gmt 0)
Fred, I think you're worrying unnecessarily. This is assuming that you've checked the 301s, and that the redirected requests return the desired urls with a 301 header response.
While I have no special inside track on Google's indexing structure, I do know that it's a very large and complex system, processing so much data that there are databases handling the order in which other databases execute various operations. It makes complete sense to me that, in such a large system, there are likely to be latency issues. I've observed myself that display of new data is liable to lag behind actual indexing.
I'm sure that among the rules in such a system, there is a routine that would prevent old redirected content, removed from the index but still displaying in the serps, from being seen as duplicate material.
Conceivably, though, if your pages aren't getting crawled, redirects of old material might not have been indexed. Have you checked your logs to see if Googlebot has seen your redirects? You might want to use "view as Googlebot", which in effect would both provide a confirmation of what Googlebot sees and also prompt a Googlebot visit.
Can you check the above and describe the situation in more detail.