I thought it would be fun to see if anyone can guess the problem I am having with a TB push mower.  A quick background on the mower - Honda motor, FWD, 21" cut.
Now, the picture below shows a line between my cuts.  I had to spend about 10 minutes figuring out the problem (which is a simple fix) on why I was getting those lines.  
It is now up to you guys to take a guess on what will cause that.  There is no 'prize' other than bragging rights. 
And before anyone says it, ITS NOT HOW I WAS CUTTING. 
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