Fingerless Mittens... I Don't Get It.

Everywhere I look I seem to find a pattern for fingerless mittens. As the cool weather sets in decided to try knitting a pair to see if it would keep my fingers warm while I typed at the computer early each morning or while knitting. I knit up a fingerless mitten using sock weight yarn and this pattern. It was an easy pattern and knit up pretty quickly.
I knit the hand portion an inch or two longer so it would go down further on my fingers.
I tried my one mitt this morning while typing and I realized something... My finger tips are the only part of my hands that get cold. Guess what part of my hand was still cold while wearing fingerless mittens. I could have smacked myself on the forehead for not realizing these wouldn't help before knitting one up. So, I won't be knitting a partner for this mitt.
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So, does anyone out there wear fingerless mittens? Do they really keep your hands warm?
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