Edit: Shortened quote to be more specific.

I disagree, I think it promotes too strict an environment. After you are in the clouds there is no reason you can't sit back and relax while you scan your instruments, the outside, your shoe lace, or anything else you feel is interesting to observe. You of course have to keep up your scan but being comfortable enough to work in and around the cockpit is a must IMO.

There are many times you will be ruffling around the cockpit looking for charts and maps if you fly IFR. You need to be comfortable and relaxed, sitting there like a stick all the time will make it pretty difficult when you have to do anything but fly.