Why vertical progression is poorly implemented

[Zumi]

That's not what horizontal progression is at all. Horizontal progression as most of us want it would have gearsets that are variable based on the situation. The whole point of it is that there isn't one ideal BiS slot. What is BiS changes based upon the encounter or party makeup. People who want things like skill trees aren't really asking for horizontal progression, they're asking for more variability in ways to build their character.

If you look at FFXI there was a BiS tp set, a BiS WS set, a BiS damage reduction set, BiS Fast Cast spell set, plus you had to swap in all the pieces of AF1/AF2/AF3 gear that had ability enhancing gear when you used your job abilities. Macros were just used to swap between all these gear sets people would use up their whole inventory with gear swaps for 1 job. Also in FFXI people were very picky about joining parties if you didn't have a reilc/mythic/empyrean weapon you would not be allowed to join the group.

Having all these gearsets just lead to a bloated inventory and way more items that you needed to be good at the game.

For example in FFXI here is a pretty updated list of the BiS sets http://www.ffxiah.com/forum/topic/46...f-defense-v20/
If you actually went out and got all that gear inventory issues and the amount of gear you need to carry around seems a bit excessive.