If you are looking at the XML export of the FIM synchronization config and you are trying to track down which sync rule is supplying a particular flow you just need to know which numbers lead you where.
<import-flows mv-attribute="accountName" type="ranked">
The key to finding the Sync rule is of course the Sync rule ID. However, this is not the resource ID that I can search for in the FIM Portal. Rather this is the metaverse ID.
From there I can open the list of connectors and for sync rules there should be one -- the FIM MA.
Then I can see the Distinguished Name of the Sync rule which is the Resource ID (aka ObjectID)
Then I can search in the FIM Portal by ResourceId and find the corresponding Synchronization rule:
Even better is to use the Join-ImportToExportAttributeFlow PowerShell commandlet originally created by Craig Martin http://fimpowershellmodule.codeplex.com/
Joe Zamora found and tweaked a minor bug in it: http://c--shark.blogspot.com/2013/03/one-small-addition-to-powershell-module.html be sure to use this fix.
Using the commandlet you can have a spreadsheet showing you the end to end attribute flow.