Thank you, BarabaraB for these keen observations of Elinor regarding Col Brandon.

That her observations about his spirits are proved correct by the information given by Sir John shows that one can rely on them.
Thankfully he is not "naturally gloomy" as both Marianne and Willoughby will have one believe.

Elinor sums it up with;
"I can only pronounce him to be a sensible man, well-bred, well-informed, of gentle address, and, I believe, possessing an amiable heart.""

The Colonel's reaction to unfortunate happenings seems to be well expressed in silence without words unlike Marianne who needs a lot of drama and "words"
It has not made him bitter. He's "mild"

Is this another way of showing sensibility?
I think Marianne's preoccupation with "words" is misleading her already where Willoughby is concerned, and she's missed noticing a man who is "reacting" so deeply to some 'misfortune'.