Okay, let me lay out my scenario. 
I have done one trade run(since the strategus update) prior to this one I am doing now.  My first trade run I had 230 troops, I bought 227 goods in town A and 230 goods in town B, a total of 457 goods.  After I bought the goods I was moving at 16m/min.
Now I start another trade run.  I have 300 troops, I bought 300 goods in town A and 300 goods in town B, a total of 600 goods.  Alas, I am moving at 8m/min now!  The only difference from trade run 1 and 2 is I have a little bit of gear on me, but its not really much than I had before.
What is this madness!  Maybe I have read the new goods/troops change incorrectly?