> This is because, as a human, you don’t activate the switch, you press the key. A measurement that starts from switch activiation time misses this large component to latency.
I would guess (and maybe I'm wrong about this) that you rest your fingers on the keycaps, and press them in as far as needed to actuate, but no further. The key still needs to travel.
Not sure how much I press them down (will try to analyse at next opportunity), but whenever I play a FPS (which is admittedly nowhere as often as I'd like these days) I certainly "preload" the fingers on the WASD keys in such a manner that the press is far quicker than when I touch type.
Precision and responsiveness is far better than using a chiclet type keyboard such as the MS Sculpt, which compares a bit to the Apple Macbook keyboards from memory (although the new Macbook Pro has even shorter travel again). The Sculpt (or MBP) has much shorter overall travel compared to the Romers, but the feel of when you are off/on really doesn't compare; the keys feel dead in comparison for gaming. YMMV.
But I see he does goes on to say that he cares about game performance, rather than typing experience: « If, for example, you’re playing a game and start dodging when you see something happen, you have pay the cost of the key movement, which is different for different keyboards. »
For me, I don't care about the time after switch activation, rather about time after the tactile feedback (the "click"). Ideally the character would appear on the screen at the same time as the click; not after, and not before. If a keyboard can 'cheat' and activate the switch before that and hide some latency, that's fine by me.
In tacticale switches the bump and the making of the contact are mechanically connected.
Using the moment of finger/key contact quite obviously selects for travel, among other things.
Nope! This is rarely (if ever?) the case. In alps switches, for example, there are two totally separate leafs, one of which handles the tactile feeling and the other of which is responsible for the actual actuation. If you browse through Haata's Plotly[1] you can see that many switches actuate well after the tactile bump. Though they are often pretty closely related in terms of their depth in the keypress, they are wholly unrelated from one another mechanically.
Cherry MX.
The tactile event on a Cherry MX Brown is ~1mm into the travel distance, and the actual actuation is ~2mm in. Kaihua Box Orange switches (still an MX-style switch) is an even better example of that. Kaihua Speed Bronze has the actuation point inside of the tactile bump instead of after the bump. I can't find any examples of switches that actuate _before_ the tactile bump (mostly because why would anyone design that?), but tactility and actuation are not inherently tied together in cherry MX switches, either.
They are both handled by a two-part leaf, which you can sort of see in some of the pictures on Deskthority[1]. There are two legs on the slider that have a surface to them that determines the tactility (or lack thereof in the case of linear switches) that slide linearly up and down the top leaf, which flexes it until it makes contact with the bottom leaf. That contact causes the actuation. All of the tactility is determined bu the shape of the slider legs.
How the making or breaking of the contact is related in terms of travel to the key press force doesn't have much to do with that.
The point I made was simply that on other kinds of keyboards the two are not related. On a rubber mat keyboard you can keep the dome depressed yet not actuate, for example. The collapse of the dome is also harder to control than the resistance against the spring. That makes preloading harder.