Speed Limited in Vertical Mode

[YorksPhotos]

Yesterday I took a few pics in vertical mode and when I flew to new location it was very slow. I thought I bumped a button. I quick scanned the manual and couldn't find anything. After a Google search I found the speed is limited in this mode. I get the gimbal limitations due to physical design but why is thespeed limited?

 

[PINEBARON]

I think its there to protect the gimbal since its vertical movement is limited in vertical mode; excessive speed would add considerable aie pressure against its vertical end stops.