That would seem to be the case.
Wouldnt be the first time the mount speed modifier wasnt accurate to what was being actually stated on the tooltip.
- - - Updated - - -
Hopefully we get a world map that is properly accurate to lore accurate sizes, instead of being accurate to in-game sizes. Always just makes it seem so weird when supposedly small island nation Kul Tiras is half the size of actual continent Northrend.