1. Emulation requires technical software knowledge, ie. it requires techies, which in turn means it requires money. Migration however can be done in-house by suitably trained staff.

2. According to strict emulation theory, we should open last year’s documents on an emulation of last year’s system. But of course no one does that: they just migrate the doc up to the new version of the app.

3. Emulation seems to mean different things at different times. It could mean

  • same functionality as the original app, but not the appearance. This is true of (say) the web-based Enigma code machine emulators. They don’t emulate the wooden box appearance of the original, just the process. Or it could mean
  • different fucntionality, same appearance. This is true of Marathon, and many other game emulations I imagine.