The question here, "is a single click faster and more productive than a double click?" The answer is 100% yes. It's faster, better, more reliable and more productive. Let the logic begin. Put 3 apps on the desktop. Now launch the 3 apps. First with single clicks then with double clicks. What you end up with is 3 clicks vs 6 clicks(2*3). Now divide 3 and 6 and you get 1/2. So a single click is by definition, and mathematically proven to require 50% fewer clicks, thereby making it 50% faster than double clicking. This assumes that every time you double click it works and we all know and have experienced that this is not the case with double clicking. How many times have you had to double click again when the first time failed? Making a double click now a quad click and forget about when it fails the third time, you get the picture. Single click never fails, only the user of the single click fails, which I will get to shortly.
Now lets discuss preference. For all those who use "I've been double clicking for so long it's faster and more efficient for me," well, this is simply not the case but a perception. And that kind of reasoning or logic should never be used but all too often it is and leads to incorrect results. Consider the automobile, before it, there was the horse and buggy. Use the "It's what we have been doing so it must be better" and we would still be using the horse and buggy, even though the automobile is clearly better. Before there was the light bulb, candles had been used. If they had used the same logic, "We've been using candles for so long they must be better, light bulbs can't be better" we would still be in the dark. This kind of logic doesn't work.
For those of you who have your apps on the task bar so you can "single click them" If double clicking was faster and more efficient you would leave them on the desktop and double click them. You put them on the task bar because single clicking is faster. 50% faster and 100% more reliable than double clicking. So those of you who put them there prove that single clicking is faster and more efficient, otherwise you wouldn't put them there.
For those who use shortcut keys from the keyboard and think that's more efficient and faster you would be correct, and of course it is compared to how you would have to get to the same place if you had to click your way to it, why do you think they call them "shortcut keys?" because they are faster, more efficient ways of getting what you want than having to click to get there. Just like single clicking is a "Shortcut" to double clicking and by definition is faster. If a shortcut wasn't faster, why would you take it? They're called shortcuts for a reason.
And for those who use the fear that they will make lots of mistakes and accidentally delete something they shouldn't, and think that's why it's better really don't understand the process. Remember, you are asked before you delete anything if you are sure you want to delete it, and that has nothing to do with single clicking. So the failure is not because of the single click, but the user.
Yes, if you've been double clicking you will make mistakes at first. Like anything new it's unavoidable. But just because you make mistakes when first changing to single clicking, this doesn't make double clicking better or faster. There is a learning curve, but once learned, a single click is faster, more reliable, more efficient and will make you more productive, hands down.
But of course don't just take my word for it, Microsoft wouldn't have introduced it if they didn't think so too.
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