Harris Tweed and WDG Style Theory

From one Mr. RB we've received a timely (due to the apparently permanent and constantly thicker white color scheme of the USA) and crucial inquiry about that wondrous fabric known as Harris Tweed: 

"Dear Sir,


I favor Harris Tweed sport jackets, usually with no tie.
Would a pocket square be appropriate with such a coarse weave and sans tie?
What about with a bow-tie?


Thanks!


RB."

This is a very good question indeed. 

I have two Harris Tweed sport jackets myself, sometimes worn with a tie, sometimes not.  With a tie, I employ a cotton pocket square or handkerchief--it's thick enough to match the heaviness of tweed, but not so heavy as to look like I stuck a piece of carpet in my pocket.  A thick silk (knitted silk, for example) handkerchief would also work.

Forsooth, that's one of the basic tenets of men's fashion--matching the basic elemental components of one's ensemble:  the colors, the patterns, the fabrics, and so on.

Onto the tie/no tie part of your question.  Without a tie, I would advise not donning the pocket square, and there's an interesting reason for this:  "Tie Theory."  This is a theory that says some things depend on a tie for their existence; for example, a pocket square, a boutonniere (button hole), and the obvious tie clip or tie chain.  There's little use scouring the internet or literature on men's style and fashion for this theory, at least by name, because I just invented it, and as far as I know I am the first one to do so (I may as well lay claim to it now).   Thus, when worn alone, these "dependent embellishments" (to coin another term), such as a pocket square or button hole, give the impression that a fellow is either astoundingly forgetful (perhaps due to having neglected the morning tea or coffee, resulting in an acute and shocking lack of mental awareness) or lacking in fashion sense.  
   

Now, if you're wearing a tie with your tweed sports jacket I would say that the pocket square isn't as important as it would be for a non-tweed suit, since tweed is a more relaxed matter; nevertheless, even with the more casual suit or jacket of tweed, a pocket square is one of those details that sets one apart from the crowd.  

Two quick final notes.  One, why not a bow tie?  The world could use more gentlemen wearing bow ties.  Two, a tie worn with tweed, bow tie or otherwise, should be a weight that matches the heaviness of the tweed and of the pocket square.  Consistency in a gentleman's ensemble is, in my book, essential.  Everything should be cohesive, so that people will say, "There's a man who has it all together!"