Granted this is only based on personal experience and the experiences of people I know. Basically people figure out the shift key in less than ten seconds and it's not an issue.
Is this really a big deal for people? It looks nice and it works well, who cares?
It seems like you can always arbitrarily argue that a certain design decision is better than some alternative - it feels more like bullshit than science.
Also, it's the job of the UI to tell the user what is going on.
So no, it doesn't work, and it would be easy to make it work. Just give it a glow or a color, like the old keyboard did.
For first-time or occasional users things like that can get needlessly annoying, and if "it's just a tiny detail" is applied to everything, it quickly leads to "death by a thousand paper-cuts".
So yes, most people probably don't care about it, but IMHO good UX design should care about tiny details and look into small effects.
Sometimes I think I'm the only person who feels flat is a dream come true. I've been waiting for this style to be mainstream for almost a decade.
The article is full of hyperbole, and I wouldn't want to read his book after reading half of this article.
nice how we went full circle with every app looking like X11 ones
Developers tend to have an analytical mindset, and people with analytical mindsets tend to overgeneralize. We find something that works for us in some cases, decide that it's the One True Way (tm), and try to apply the same principle to everything. We defend our choices religiously, blindly pursuing the ideal of purity. If any user dares to admit that they don't understand the reasoning behind our elegant designs, we blame them, not ourselves. PEBCAK, after all.
Then a new trend comes along, and we repeat the cycle all over again.
In fact, the problem does usually exist between the chair and keyboard. Except it's not always the user's keyboard and the user's chair. Sometimes it's between our keyboards and our chairs.
It is true, the default theme ("Material") of the google keyboard has no borders.
But, anyone can change to another theme ("Holo" theme has borders). And a lot of Android users use another keyboard app, either by choice (SwiftKey is popular, and has borders) or by default (Samsung phones have Samsung keyboard by default, not google keyboard, and it has borders).
