Well, no. That's not true... I'd freeze. But I am getting tired of my Winter wardrobe routine:
t-shirt --> crew neck sweater --> quilted vest --> outerwear --> scarf --> pray it's not too cold out because I don't look at my weather app before getting dressed...
It's just time to layer differently. Topcoats are so last week. ;P
Thankfully, with denim jackets becoming more and more fitted , it's easy to use them as a layering piece rather than an outerwear piece. Example: a denim jacket under a blazer, paired with a shirt and tie. It's office-casual, yet fresh. The denim takes the place of a thick sweater and rides a line between rugged and dapper. Another example: a denim jacket under a long cardigan (see above, obvi). The cardigan replaces your topcoat and you are still layered up enough to stay warm. It's cozy yet edgy.
Now, let me be clear, I barely consider a denim jacket outerwear. You can wear it well into the Summer and most these days are lightweight. It's a pretty versatile piece of your closet.
At any rate, find yourself a thick, long cardigan and a giant blanket scarf, and you'll be set for Winter layering in a whole new way. As long as Juno isn't on top of you.... Then by all means pull out your parka, or stay inside like I did.