13,
I've had no problem with the panels flexing as the parameter of the panels are secure. It would take a high wind to cause problems, IMHO. My panels are 40 inches wide X 65" long, including the superstrut frames and only have 4 inches slope on the 40" side. We have 100 mph winds every 3 or 4 years.
I intend construct a sloping back on my frames to form an inverted "V" if I have to have more power from them later. I think if I do have wind problems, it will tend to peel my laminates off the superstrut from the wind pushing against the parameter from the back side.
If you want them to tilt with the seasons, you could construct the sloping wall part of the "V" and put hinges on the lower frame member of the panel side. I hope this is a bit clearer than mud.
Check out Oztules construction methods also.