Out of course; by the way; not connected with the subject.
Jumping, or passing, from one thing or subject to another, without order, planning, or rational connection; lacking logical sequence.
Disappointing in performance or progress.
(of a speech) moving from topic to topic, not focused
The readers were expecting things to be a little more direct, and so they're probably feeling a bit flounderish.
that flounders; that moves with awkward struggles