[SoftwareMaven]

Forcing the typing a command character on a ten-digit phone pad might have caused enough friction to have put Twitter on a very different trajectory early on. Given how long Twitter has had this feature and how little issue it's caused, I would argue it was good product design.

[hesselink]

Perhaps duplicating the first letter would have been a good idea. So 'gget', 'ffav' etc.

[treetrouble]

good design implies that there's some advantage to its use

[tedunangst]

? I can use a simple command to request tweets on my dumb phone. How is that not an advantage?

[treetrouble]

Is it not still simple with a single character prefix?

[tedunangst]

Depends on your userbase. Completely in band normal English command messages probably fits many users' mental model.