Look. Today I raced another wood elf. He was wearing the same armor: Fiord's and Cowards Gear. Movement speed bonus to sprint. I was mounted. MY MOUNT SPEED SPRINT WAS THE EXACT SAME AS HIS ON FOOT SPEED SPRINT.

I raced a fellow (NOT an orc) with regular training gear, no movement speed buffs. He was mounted, same as I. Both of us have our mount speed maxed at the trainer. WE WERE THE SAME SPEED.

People, there is something drastically wrong with this. They say MOVEMENT SPEED applies to riding speed as well, but clearly there is something wrong.

When the devs "invented" Major Gallop as a separate buff, all other sources of expedition (major and minor) stopped to work while mounted, when they used to until that point.
That was some time ago, i can't precise exactly when but it's been like this for at least 2 years.
Also all sources of movement speed now apply exclusively to your character on foot and not while mounted.

Major and Minor Bummer buff were then applied to our characters, as Rapids became the only way to increase mount speed on max level mounts.

Of course Minor Gallop was never sourced, they missed the occasion when they reworked one of the Cyro sets that used to give mounted speed bonus on the 3d piece, can't recall the name now.

It's called performance improvements, enjoy