The staff member made the comments about the new MP4-27 single seater before it was launched by the British team at its Woking headquarters on Wednesday.
The story was only live on the internet for a short time before it was removed.
After that, members of the media were contacted by McLaren insisting that the quotes had not been accurate.
The saga caught the attention of the widely circulated German newspaper Bild, which wondered: “(the risk of a) protest? So maybe the car is illegal?
“The rivals will now be looking very closely (at the car) at Jerez,” wrote correspondent Frank Schneider.
He said the MP4-27 has “mysterious lumps” on the side, perhaps to “hide the exhausts”.
Spanish sports newspaper Marca’s correspondent Marco Canseco, meanwhile, said the new McLaren is “not revolutionary” at first glance, with the disappearance of the L-shaped sidepods of last year even indicating a “backwards step”.
The exhausts, however – with blown diffusers now banned – were “very well camouflaged” at the launch, “embedded in a strange bulge” at the rear of the engine cover.
The diffuser, added Canseco, is “nonexistent” in the MP4-27’s launch version “to avoid clues being given to the rivals”.
2008 world champion Lewis Hamilton, meanwhile, laughed as he revealed that McLaren answered his call for better mirrors in the wake of several incidents last year.
He said the new MP4-27 mirrors are higher and “don’t flap around”, joking that “Felipe (Massa) will be very happy about that”.