Comment by ctbeiser

The problem with modes is fundamentally that people make mode-errors; they're not sure what mode they're in. If you've got users who aren't looking at the device, then yes, they'll make mode errors, because they have no clue what they're doing. If it's an unambiguous mode, and people understand the ways into and out of the mode, sure, you've got no problem, but those conditions are typically only met by system-level conventions.