I thought taupe was that weird pinky mushroom color. I like this a lot better.
From my rather limited familiarity with covert, I'd figure that something a bit less tailored would be in order, because good luck holding a sharp crease. I picture the darker winter variant of a tan poplin sack suit.
I guess there is no waistcoat, which is probably for the best.

 

From Wikipedia -

https://en.wikipedia.org/wiki/Taupe

"When viewed on a precisely calibrated monitor, the color displayed above-right matches the color sample called taupe referenced in the 1930 book A Dictionary of Color, the world standard for color terms before the invention of computers. However, the word taupe may often be used to refer to lighter shades of taupe today, and therefore another name for this color is dark taupe."

Another example -

 

I really like that taupe, though I never cared for covert twill in a suit. Covert twill is great for topcoats and trousers. In a suit would it just be an alternative to tweed?

 

I'm used to taupe referring to a salmony type of dark tan, a pretty awful color usually.

or

at best. Nauseating neutral.
I'd never heard of a covert suit. Is this something done with even limited regularity in custom, much less RTW?
I could go for it as a beefier unfuzzy flannel substitute, I guess.

 

I really like that taupe, though I never cared for covert twill in a suit. Covert twill is great for topcoats and trousers. In a suit would it just be an alternative to tweed?

Yes and no. Its origins are similar to tweed in that it was worn for sport in the country, and it's certainly more rustic than worsted, and possibly flannel too. But as evidenced by the photo in the OP, it can be dressed up a bit more easily being sleeker than tweed. And I'd suggest more wearable as town wear. In its stouter form it's fairly heavy and durable cloth, but it has a naturally beautiful drape, and as twills often do tends to have a bit of elasticity making it innately comfortable and a cloth that molds itself to the body. It's also a bit of a paradox in that its appearance is both distinctive but discreet.

 

Thanks for sharing, to tell the truth I had no idea about taupe, no doubt dark taupe is good and a very good addition to any wardrobe.

 

The father of a friend from student days (c.1980) wore exactly such a suit. A lot depends on the exact shade of the twill, but covert cloth can have subtle qualities. I have two pairs of trousers made from it - one pair I like very much, the other less so as the colour is just slightly off, too much like British Army khaki.

 

The father of a friend from student days (c.1980) wore exactly such a suit. A lot depends on the exact shade of the twill, but covert cloth can have subtle qualities. I have two pairs of trousers made from it - one pair I like very much, the other less so as the colour is just slightly off, too much like British Army khaki.

I now have only two items of covert cloth, both trousers. One is a mid greyed-tan arguably a shade now most often referred to as taupe, but the other is made of a marled yarn consisting of olive and black. The result in the later is cloth that is a very dark grey-olive shade, and quite unusual. Looks very nice with brown tweeds, and many other jackets.

I think your characterization of the cloth having subtle qualities is spot on. Evidently the marled yarn is composed by spinning two different colored threads together, and the yarn is then woven in a particular twill process.

 

As I mentioned, one of the nice things about covert cloth is how well it blends with other country cloth and many colors. It's not always easy to wear a tweed vest due it's texture and often accompanying patterns and colors. But covert cloth has a natural affinity to tweed.

Here's the suit again -

And here's an Harris Tweed waistcoat that might do nicely with it -

And of course it can look very good with moleskin too -

(Ben Silver)

And it can look terrific with the right tartan -