Tag to Tag?

I was wondering if it's possible to alter the format of existing tags in the way that the feature filename-filename works? For example, for a list of album titles to change the names using dummy variables. At the moment, the only way I can do it is to copy the filename to the 'comment tag' so that it's not lost, do album tag to filename, then use filename to filename (with new format) and export filename back to album tag... finally export comment back to filename to have original filename! Hope that makes sense... Any ideas? It would be a nice feature to have...

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There should be several possibilites like "Guess Values"

Thanks, I'll give it a go!