*Really* fitted with never a wrinkle?

I am in Yorkshire*, and yesterday had lunch at a pub** called The Highwaymay. The lunch was delicious, but obviously I had to read the poem and found myself reflecting on his clothing:

He’d a French cocked-hat on his forehead, a bunch of lace at his chin,
A coat of the claret velvet, and breeches of brown doe-skin.
They fitted with never a wrinkle. His boots were up to the thigh.
And he rode with a jewelled twinkle,
His pistol butts a-twinkle,
His rapier hilt a-twinkle, under the jewelled sky.


So now I need to know, can doe -skin breeches really fit so well they never wrinkle and yet you can get into them and also bend your knees? Is that why he was wearing thigh-high breeches, so he only had to have unwrinkled breeches visible over the bit of conveniently-shaped thigh? I know that very fine leather can be supple and a bit stretchy and I've some very well-fitting gloves in it, but the practicality and pattern layout of skin-tight breeches is a subject asserted but seldom explained in literature. Enquiring minds want to know!

*Where it is showery. Yesterday we sheltered under a garage wall, which provided a dry patch and also a very large number of enormous wasps. Fortunately in placid mood.

**In Lancashire. There was a sign on the road. We are staying on the edge here.