[Bonooru]

I type relatively quickly (95 wpm) and I didn't even notice the delay until "really not great" (100 ms) and it didn't bother me until "we're done here" (200 ms). I think it has more to do with expectations than it does anything else... A "slow" text box just isn't that annoying. I'm usually waiting for my fingers to catch up with my brain anyway, so there being an extra few ms doesn't change much. It's a little disconcerting to see the text all catch up at the same time and back spacing at the slowest setting was annoying. But still not seeing what the big problem is.

[zokier]

I suspect delay impacts more slow (or error prone) typists who rely more on visual feedback, whereas fast typists presumably generally rely/trust more just physical feedback.

[asark]

I'm probably still easily in the 80s WPM, and could practice back up into the 100s in a day or two. Input lag doesn't so much throw off my typing as it makes computing feel kinda remote and gummy rather than real and crisp. You lose the feeling of a direct connection between your input and the computer. Like you're poking the keys with a stick underwater, no matter how fast you type.

Even this text box, on HN, is noticeably disconnected compared with, say, DOS on an IBM PC-XT, or your average text input area on early Apple computers, BeOS on a first-gen Pentium, QNX on same, that sort of thing, and that's without applying the linked site's extra latency. Everything, just about, is a bit muddy on a "modern" computer. iOS is the closest thing to an exception and even that's gotten worse over the years.

[jdietrich]

I'm a fast touch typist, but input latency really throws me off. If there's more than about 150ms of key-to-screen latency, I'm faster with my eyes closed. I normally scan the screen as I'm typing so I can quickly backspace over a typo, but I find it really difficult to plough ahead if the screen isn't keeping up.

I've had a similar experience with audio systems - I can play guitar tolerably well even if I can't hear what I'm playing, but >40ms of latency will turn me into a ham-fisted mess.

[structural]

I'd tend to agree that it matters the more you rely on visual feedback. I type on unfamiliar keyboards a lot and use visual feedback almost exclusively; 10ms latency was imperceptible, 20ms was very noticeable, and the 50ms latency was at the point of being unbearable (I'd go find another machine to work on or something before typing with that for more than a couple minutes).

[waqf]

Also it impacts cursor editing (for example using vi) more than just typing text, for the same reason.

[war1025]

Wasn't vi invented specifically for dealing with high latency networks?