Nissan & their fanbois were bragging about the new GT-R... long before it reached production. Nissan's marketing team compared their GT-R, a semi-luxury 4 door coupe, to a real Sports Car.
Nissan runs a "RINGER" @ Nurburgring and issues PR bragging about the ~7:38 lap time.
Then... they issue another PR... with the fabled ~7:29 lap @ Nurburgring.
Porsche buys a "stock" GT-R, and is unable to come close to the ring lap times reported by Nissan.
Car magazines also test "Stock GT-R's, and get the same results.
When Nissan releases the GT-R to the public, their customers experience a rash of tranny failures. Nissan denies warranty claims, even for turning off the VDC (Vechicle Dynamic Control). Looks like Nissan used the electronic gizmo's on the GT-R to reduce drive-train failures.
All in all, this adds up to:
A. Publicity nightmare
B. Casting doubts about both Nissan's Halo car... and Nissan's credibility.