I'll have to inject a bit of criticism to this particular rant.
If one is using several applications on Windows and being productive about it - You don't switch applications in Windows by clicking then with mouse. You order them on the task bar and then switch between them using windows button - number (where number is the order on the task bar.).
I routinely Alt-Tab between my current 2 or 3 windows when working, but i often have 20+ windows open at a time across 2 monitors and often times I will SEE the window I want right there, but selecting it is nigh on impossible.
One of the biggest culprits is MS Office (especially Excel, where I routinely keep data i need to refer to every now and then). Unless the title bar of the window is visible, clicking on any other edge will change the current active tab, pull down a menu, open a dialog, disable recalculate mode or some other weird behavior that is sometimes not readily apparent.
Ah, yes, with that workflow I'll have to agree. I can timesplit my work so I can always arrange the windows to taskbar and have generally less that 9 windows to deal with in single task. Context, context, context.
Depends on what you're doing. Direct visual manipulation is best if you're using the mouse. Winkeys can be better if you're primarily trying to stay on the keyboard.
I actually researched this back many years ago, and at the time, clicking on windows Exposé style won out reasonably convincingly over keyboard techniques, including winkey+#.
"best" and "won out" how? Certainly not in speed. Win+# is O(1) in complexity and I already have my left hand in position to press the 2 buttons required to instantly get to the window I want.
Compared to expose which is first a hotkey to initiate(note that already here you lost the race in number of keys to press), wait 300ms for the animation to complete, find the window you want which is more like O(n), move hand to mouse, move mouse around to find the cursor, move cursor to desired window, click, wait another 300ms for animation.
Even if I happen to already have my hand on the mouse and know where the cursor is the best case will take you at least one second, this is much inferior to just pressing 2 keyboard buttons which is essentially instantaneous, even with faster animations you will not save much time as you need that time to find the window. With more than 5 windows open finding the right one can be a true challenge as they get very small and there will be a lot of them to scan.
For grandma who don't care about speed maybe expose is easier to understand and remember but for intense task switching by experienced users it is just in the way.
An Expose-style interface with short animation beat all other interfaces (taskbar click (window), dock click (app), winkey+#, alt-tab) in mean task switching time over a series of controlled scenarios (not the user's normal workflow - just simulated scenarios). Expose style interface was invoked with a side button on the mouse.
From memory, Expose was around ~1.0s, taskbar click around ~1.2s, winkey around 1.5s, with other methods slower.
The physical action of flicking your wrist and clicking is actually surprisingly fast, possibly even faster mechanically than a two-key keyboard shortcut - think how fast twitch gamers are.
Decision time was the main component. Expose's decision time was the lowest mean, and the most stable. Alt-tab had the lowest decision time, but far greater stdev. Yeah this is a controlled test that may not represent a real user's workflow, hence my 'depends'. "Find the window" is actually an interesting one - as long as the interface is reasonably spatially stable, you actually don't need to find it because your spatial memory takes care of that for you.
In my experience, while I might have a few 'primary' windows that suit the ordered taskbar well, I've often got a number of other things that come and go. I'm never going to remember what place they are. So, while winkey+# is fast for a select few windows, it's really slow for others. I don't find it appreciably faster than an Expose interface, and it's easier and faster for me in my workflow to use one main task switching interface.
When I say "decision time", I'm really referring to everything between "I need to switch to a window", and "I have just started performing the action needed to switch".
If one is using several applications on Windows and being productive about it - You don't switch applications in Windows by clicking then with mouse. You order them on the task bar and then switch between them using windows button - number (where number is the order on the task bar.).