I use Avid at work, and I'm accustomed to marking my in and out points, inserting or overwriting, then continuing to JKL to the next shot. Generally don't use the mouse, at least not while making basic edits.

In FCP, which I'm using increasingly at home, I notice it switches focus to the timeline every time I make an edit. I can hit "Q" to shift focus back to the source, but is there a away to make this it keep the source window focused by default? Hope this makes sense. Thanks.

Hal
Your best option is to use a third party macro tool, programable mouse or similar. Using such you can create a single hotkey for Insert that sends F9 + Q so that window focus is switched back automatically. Same goes for Overwrite.
As it stands, the only way to maintain focus in the viewer after an edit is to use a mouse based method, specifically to drag your marked selection to the Canvas window overlays.
Andy