Ok maybe that intro is a bit of an exaguration, I mean where would I be without Ctrl-C / Ctrl-V, or even the meta key as a standalone is a kind of short cut I guess..
Anyhow, despite staring at a windows UI for years, I've only just realised that Meta-Tab is a way better way to get around. Gnome, Cinnamon, and KDE have had this kind of stuff baked in forever, but like so many people I'm locked in with windows as far as a work machine is concerned. (Thanks very much Auskey Credential!).
Anyhow.. Aero Peek is the thing that happens when you hover an application on the taskbar.. you know, you're shown a small tile for each instance of that application, which helps you choose what you're looking for. Meta-Tab pulls up task view, which I won't bother explaining because you've probably already seen it, but obviously it's much more suited to this purpose because each application preview is big enough to actually see what you're doing in that instance.
The difficulty now is to actually change my habit to go for Meta-Tab instead of mousing over the task bar without having to think about it.