Switch Types

There is hysteresis in nearly everything you use. If there weren't you would get terrible chatter by holding it at the point of connection. The hysteresis doesn't need to be large or even noticeable. If it's not noticeable you won't notice it.

Exactly. What people are forgetting is that even in a mechanical switch the switch contacts typically have nothing to do with the feel of the switch. The contacts are lightweight springy leaves and you don't feel them when they make. The old railroad key I have uses the contact for the bottom stop, but it is some black material and I expect depends on significant current to keep the surface in condition to operate properly. I doubt it would continue to work if the current were reduced to a mA or less. I need to dig it out and take a closer look some time.

I have seen a keyboard without a travel click, where they had used a small speaker to sound the strobe click of the keyboard.

Strangely that click caused a feeling of feedback.

I used a solenoid to whack a metal plate with membrane switches on when you pressed one. It was fun, but didn't make it to production because it was felt the customers would laugh. We all did.

Cheers

A very sick feeling, maybe. There is a reason even cell phones add haptic feedback. It's not great but it's better than nothing.

The pinnacle of keyboard technology is the IBM buckling spring, though.

that could explain my experience with them. I've avoided the things ever since. I don't suppose you remember when this was?

NT