Yeah, I would thing loose steering could cause some wobble. That much where your buddy could see it but you didnt feel it so much I dont know. If he saw more than you were feeling then it is prolly outside of the steering joints, more to the hub and wheel. If it was steering you would feel and see it in the steering wheel, back and forth jerkyness (is that a word). But outward of the steering joints, hub, bearing, wheel and tire the steering gear would remove some of the wobble so you wouldnt feel it as much. But it could look bad for an observer. JRI jacked up the car and checked compliance on the wheels. They felt fine, there was a little bit in the vertical plane, but it seems normal to me.
When I was driving that time I had a lot of slop in the steering, I have since adjusted the steering box to remove most of it. Could the slop have caused this? Also, it could be a bent rim or messed up tire. I am going to try and have someone else drive it while i watch to wheels.