The Centurion and his horse questions.

[Magnus]

In support of the theory that Centurions (or perhaps senior Centurions) might travel to consult with the Legion commander while on the march I found this from Book 3 Chapter 5
of Josephus

"6. This is the manner of the marching and resting of the Romans, as also these are the several sorts of weapons they use. But when they are to fight, they leave nothing without forecast, nor to be done off-hand, but counsel is ever first taken before any work is begun, and what hath been there resolved upon is put in execution presently; for which reason they seldom commit any errors; and if they have been mistaken at any time, they easily correct those mistakes. They also esteem any errors they commit upon taking counsel beforehand to be better than such rash success as is owing to fortune only; because such a fortuitous advantage tempts them to be inconsiderate, while consultation, though it may sometimes fail of success, hath this good in it, that it makes men more careful hereafter; but for the advantages that arise from chance, they are not owing to him that gains them; and as to what melancholy accidents happen unexpectedly, there is this comfort in them, that they had however taken the best consultations they could to prevent them. "

Of course it an assumption that Centurions are involved in counsel but they are the Commanders most experienced officers.

John, your quote doesn't say anything about Centurions meeting the Legate while on the march. Your quote simply states that before the Romans do anything, they plan it first. Indicating that it is prior to executing the action. Which means they would have a plan before going on the march, negating any requirement (save an emergency) to meet while on the move.