Twitter is very reluctant to find out how much removing OAuth 1.0a (and their previous incarnations like XAuth) will break in their legacy infrastructure and fo

Twitter is very reluctant to find out how much removing OAuth 1.0a (and their previous incarnations like XAuth) will break in their legacy infrastructure and for existing trusted clients. A migration path would mean adding OAuth 2 in addition to all the previous mechanisms, and then likely acting over a long migration timeline.