Maybe it's the correct use of the Lydian Mode.
Using a flatted seventh as a scale note in especially moving to the IV chord. It's very noticeable to people that are trying to play along. It's kind of like the bad habit of guitar players playing sevenths all the time and claiming they're "blues players".
If you're conversant on "Garth Brooks", the correct usage of the Lydian Mode is the fiddle line after the words "Holding You".
I have a couple examples on Bobbe Seymore's Priceless CD that caught my ear, and since he's one of my best friends I don't mind busting his hump a bit. It'll make it all that more memorable when he cuts me to ribbons one day..
If I were in person,, or I was in the mood to go through plugging in and editing a bunch of stuff I'd just post the difference.

EJL