High riser thing a fad? The only reason it will go away is because of sleds like the IQR where the steering post is higher on the sled, requires less of a riser cause the bars are already up at a good position.
I just installed a 7" RSI riser setup on my 08 Shift with IQR flat bars. I LOVE it. I could almost use an 8" but cannot justify the expense of changing. Looking at all my cables and hose, I could get an 8" no problem on my setup. However I have an RSI throttle block, and repositions most everything. The IQR bars are a little narrower than my previous setup so the controls are closer in to the riser.
In slow, fast, or whatever riding that thing is perfect for me. Hell the guys I rode with this past weekend were all sit down riders and they commented how amazed they were I could ride like I do, through what I do, and stay planted on my sled. The riser is part of that. Good grip allows for using your arms to keep you in position.
Try riding standing straight up all day. Even being slightly bent over for a too short riser made my back hurt bad by the end of the day.