They do, although the 'not including nipple head dimension' could be a bit clearer as to what they're talking about. Once you know it makes sense, but it's not exactly obvious to the uninitiated.
That's what got me. When I actually measured it it became clear what it was, but I hadn't clocked it when I ordered the rims. Luckily I waited for them to arrive before ordering spokes!
They do, although the 'not including nipple head dimension' could be a bit clearer as to what they're talking about. Once you know it makes sense, but it's not exactly obvious to the uninitiated.