He adopts a high, slightly arched-back posture with the harnessBroke out the harness an acquaintance made for me years ago for my first Dobe. This is a dogsledding harness. What's the matter, Oji? Cat got your pull?
He'll get used to it and bear down like normal soon.
Actually, sometimes when I am carrying my daughter and walking him (no, it's not an enjoyable experience) she actually stands on the lead for periods of time.
Oji won't chase it much if I just swing it around without me spinning around too. 
I got it off amazon 

Of course I won't mind at all if Rumor looks like her momma.