I feel your pain. Mine cuts like crap too, leaving uncut strips just to the right of center. It's like the wind from the deck is blowing the grass over and the blades can't lift it and cut it.
I complained to the dealer and he gave me a set of high lift cubby blades, they don't work either. I sharpen my own blades very well, and they don't still won't cut that strip of grass. My previous old Ford YT16H would cut like a champ, even with dull blades. When the blades got dull, the tips of the grass started looking frayed. It NEVER left uncut strips like this one.
I don't have the mulching plug installed. I mow wide open.
I think my problem might be related to cutting on the #6 setting. I like to cut the grass high so it looks better and seems to last through the drought better. I noticed if I go down to 4 or 3, it cuts better but still ain't perfect, but I want it to cut correctly at 6 dangit!
Maybe I'll check the level at the #6 setting. When I set it, I used #3 or #4 height. It should be slightly low in the front, right? About 1/4" or less?
I hate having to cut my lawn twice! It's bad enough running over it once when it's dry like this...
If anyone has found a solution to this problem, I'd really be interested in hearing it. I'm about this close >< to dumping it and going for a green machine, which is what I was going to get in the first place. However, I found that the CC had more features for the same price. I'm thinking I was hosed...