houchin,
yep, you're right... sort of...
i just tried printing two 4x6 photos 2-up. it did print them 2-up, but they were reduced to 3.75 x 2.75.
so, following that logic, i tried printing them 2-up as 8x10s. this time they were reduced to 6.125x4.
so, that method does work, in a...