Just turn off the 3D, that's what I'll do. No stereoscopic depth perception makes that an easy choice.

Not being able to hold the system still is what hurts my DS experience.  I can't help but move controllers a little bit while playing.  With the screen being on the controller that makes it pretty damn disorienting.  And this is going to be worse than that?  The 3DS, unfortunately, really does not seem up my alley.

Obviously I'm no expert on the subject, but I don't think this will really be a problem.  If you move the regular DS around too much you can't see the screen and no one complains about that (except for Ian, but if he can't play the regular DS I'm not sure why he expected to play the 3DS...)

So is the 3DS unplayable in the small space between the "perfect position" and beyond the best viewing angle of the screen itself?  And for how long will your 3DS be in that position anyway?  I can see maybe jerking the screen in an intense moment, but I doubt your eyes remain focused on the screen the whole time and besides, it only takes half a second before it's back in position.  I just can't think of many situations where this will be a problem.

Oh yeah, and remember that Nintendo put motion controls into the system itself.  If this were such a problem I don't think they would encourage players to move the system around.