How not to do a web update

If you’re a major company and your various web-based services have evolved over time, you may have a proliferation of user IDs and some other issues to tidy up. You may be tempted to have a major overhaul. If you think your reputation among your customers isn’t low enough and you desperately want this update to be an unmitigated disaster, what should you do? If you’re dropping subtle hints about moving towards a Software as a Service model, how can you remind people about the excellent reasons that exist for avoiding dependence on on-line services in general, and on yours in particular? …