Thick and Thin
We were always taught to use a ground yarn that was 1/2 the size of the "pattern" yarn (or was that vice versa?). However, as you know, we have a yarn inventory plan. We first built our 8/2 inventory, since we love making dish towels. Now we're ready to add inventory in other sizes. We're testing whether we want to do overshot in 10/2 and 5/2, but that would require lots of new yarn since we primarily have 8/2 and some 3/2. 8/4 is similar in size to 3/2. Of course, you need to consider the different texture of a 3/2 perle cotton vs 8/4. The advantage to 8/4 is that you can buy it in matching 8/2.
So we're trying to decide, can we be happy with 8/2 and 3/2 (which is a wee bit fatter than 2x). We had planned on getting rid of 8/4 and only inventorying 3/2. But it's not too late to switch to Maurice Brassard 8/4 with limited 3/2 (we actually like the texture of Maurice Brassard 8/4).
This experiment of 10/2 and 3/2 looks so good on the loom, we'll see what happens after the magic wash.