I always have exactly twice the amount of sourdough starter that I need when I make bread. This is just a consequence of the need to feed it and the limit of size that my vessels have. It's not a huge deal - I just throw a bit out.
But the other day I decided to try doubling the recipe instead.
I reasoned that although this technically exceeds the "flour power" of my kitchenaid, the dough isn't really all that tough and kneading a double recipe is only fractionally harder than a single recipe. So I wasn't worried about burning out my motor. And the volume of the bowl is large enough to just hold the doubled dough (with maybe a little doming at the top), so I figured I was also OK on volume.
Well all of those assumptions are probably correct. But what I did not consider is that the action of the dough hook is very volume sensitive.
Let me save you the trouble of this experiment. The dough creeps rapidly over the top of the dough hook and you have to stop and unstick everything about every 10 seconds.
Plus it is quite challenging to form 6 pounds of dough into two large loaves (that barely fit onto a large baking stone) and get them into the oven and baked. I managed it, but only just.
The bread turned out well, but I won't be doing this again.