No one on our team has done one before, so a learning curves has been tested. This is basically a 700 lb., 16 ft long i beam. After we had the tables figured out, how to slide them and lock them in, we tested with a seated person. What we found is when your knee hits the i beam because of its "T" shape at the top and bottom, in this case the bottom being the knee whacking culprit, we had a mad Russian iron worker come in and weld away the bottom "T". This gave clearance for the knees on both sides.
Please mote: Anyone over 6'8" might still whack their knees. Good thing I am not a Phoenix Suns fan. Ok, their growing on me.