Spot the fake:
Well, it turns out (quite devastatingly) that the whole thing was a con. I had completed the mitten cap and was about halfway through the thumb when I asked Tim to try the mittens on, again, for the umpteenth time. And he told me that it wasn't me, it was him, it wasn't that the mittens were too small, just that his fingers are too long.
And it is true, they need a bit more length before the thumb gusset starts and to be a bit longer overall (although I had already added six rows in the mitten cap). I was loving this project. It is one of the finest gauges that I have knit at and with recycled yarn to boot and it was coming along so nicely, or so I thought. I cannot bring myself to frog them and thankfully have enough yarn to simply start again. It will also give me an opportunity to go down a size to 2mm needles to knit the ribbing. I've already bought the needles for the purpose, I just have to take a small rest while my broken heart recovers.