Originally Posted by hendrix
why is it irrelevant?
Because this is about a minimalist dressy wardrobe, and t-shirts are not dressy.
Forget jackets - what about socks? For the average man in the average situation, white athletic socks are fine, because they work with sneakers, and sneakers are usually fine. But if they need to dress up, sneakers are not fine, so athletic socks are not fine. Therefore we wouldn't tell someone to stock their dressy wardrobe with athletic socks, because the assumption is that the thing they go with (sneakers) are not part of the consideration.
By the way, everyone saying a worsted navy jacket is not useful is crazy. I keep one in the closet at work precisely because it literally coordinates with every combination of shirt and trousers that I wear to the office. So on the odd occasion where I have an unexpected meeting with someone for whom I feel the need to dress up slightly, I can throw on the jacket without even thinking about what I'm wearing that day. Maybe I won't win points for creativity, but I will look well put together. For the average man, that is all they need.
Grey jackets are much harder to coordinate properly, and are therefore less useful in a minimalist MC wardrobe. Sure they look good with jeans, but not necessarily with grey trousers. Since this is about "dressy" clothing, the jeans matter a lot less than the trousers.