https://bugzilla.redhat.com/show_bug.cgi?id=1119967
--- Comment #6 from Yohei Yukawa yukawa@google.com ---
Why do you think Direct input mode is a better choice?
Please ask him. But I suppose that IBus developers no longer want to handle tricky requirements from Japanese input method users in IBus side.
For example, please try to assign Ctrl+J to switch to Hiragana mode of Mozc from any other input source that does not belong to Mozc. According to the following thread, it is still unable. https://code.google.com/p/ibus/issues/detail?id=747
This is one of the examples why the weird Direct mode of Mozc is still required. If the Direct mode belongs to Mozc, it is easy for Mozc engine to implement those functionalists because all key events are forwarded to Mozc engine even in Direct mode. But if we remove the Direct mode from Mozc, you simply lose existing functionality until IBus issue 747 is resolved. Even if IBus issue 747 is resolved, you are likely to need to customize Ctrl+J in IBus settings, not in Mozc's one. I'm not sure if it is really useful and understandable for users.
Hope this helps you to understand the current situation.