Absolutely. I did it while riding through the empty sections of rural four-lane. It does affect the bike's balance as noted elsewhere, but the change mostly seems to be a bit more top-heaviness as if you are riding with an double-size fuel tank. This riding position is by no means intended to be a solution for optimal handling. It is merely a way to stretch out for a minute or two on straight empty highways so you can resume your normal position of control with greater comfort. Of course, we don't have to tell any long-distance rider how to position or stretch. Your body tells you when it needs a break.
I did 1000 miles in 24 hrs back in '85 on my '84. Inspiration came in the form of our fathers telling us of their 1k in 24hrs. on '65 superhawks. Our group of 6, '83 VF750F, '84 VF750F, '82 GPz750, '83 Kz750, GS550ES, and an FJ600 left the central valley in Ca. and spent the night in Rock Springs Wy. 21 hrs. later. Went over the Sierras and grabbed US50, took that to Delta Ut. then skirted Salt Lake City and finished the day on the Interstate. Toured Yellowstone the next day (another 400 miles or so). I don't think the "bun burner" was sanctioned yet, but our buns were burnt for sure! All this to say, we are hoping to do a sanctioned bun burner this summer. This will be the second for my "old girl" and the first for my son. His grandpa was on the FJ600 back then and is on an FJ1200 now and we hope he can make the ride with us! If we make the ride I plan to take pics and share here.