There's a good article about Amazon implementing this feature for their mega menu. Blew me away when I first read it, it's very obvious and simple in hindsight.
Yes, there are some great tips. I still think this style menu is just bad, though. Although certain tweaks can improve the UX, it's still an frustratingly unusable interface for people with certain motor disabilities and even just older users whose mouse/trackpad skills are not great.
At this point, the department menu is an alternative to search. It doesn't need to be universally accessible or forgiving to poor motor control, because in terms of footprint it is tiny. I have used it before and it was just fine for me, and if some proportion of their customers have a similar experience, then it seems well worthwhile.
I completely disagree with this sentiment. Everything in a UI that you can do with a mouse should be tolerant of disabilities that people who use a mouse might be going throug (tremors etc). A user shouldn't have to try to do something and become frustrated in order to discover that it is "not for people with poor motor skills". We should do better. What you describe as "well worthwhile" still strikes me as woefully incomplete and annoying. Every user could potentially have poor motor skills at some point due to temporary causes.
It's not the end of the world of course. I just wouldn't think of "I have used it before and it was just fine for me" as a good reason to not strive for a more universal approach to interface design.
> Everything in a UI that you can do with a mouse should be tolerant of disabilities that people who use a mouse might be going throug (tremors etc).
Why? Should we give up on first person shooter games? Set minimum mouse target sizes for RTS games? The point of the department menu is to convert dexterity into information rapidly. If you lack dexterity, that's no strike on your character, but it somewhat defeats the purpose of a dexterity-limited input. There is an alternative to the department menu in the left side of the search bar, which has a simple list.
That technique was used long before Amazon used it. Actually, the first comment on that article confirms this: Bruce Tognazzini came up with it for Apple in 1986.
http://bjk5.com/post/44698559168/breaking-down-amazons-mega-...