To clarify that this so-called Easter egg won't be limited to an amusing display on the vehicles massive console touchscreen like, for instance, the Mario Kart Rainbow Road or the existing Ludicrous mode animation, he added a couple more hints.
First, he elucidated that the P100D isn't, actually, left-handed – a reference to a sword-fighting scene in the movie The Princess Bride in which one (or more) of the dueling participants reveals he has been sandbagging his performance by not, at first, wielding his weapon with his dominant hand (see clip below for the full, amusing, scene).
He later went on to explain that this isn't the "Plaid mode" – the very ultimate in acceleration according to the movie Spaceballs, from whence the term "Ludicrous mode" also originates – that we've been told to expect in the next-gen Roadster, but might be considered a "light tartan."
Although no time frame was initially given for the roll out of the go-even-quicker Easter egg, Musk later tweeted back to an inquiry from @DragTimes that it might have an "early access release" ready for the outfit's SteetCarDrags event taking place this upcoming Sunday, the 13th, at the Palm Beach International Raceway. If it arrives in time, we expect to see some records fall.
On a related note, Musk also hints that the Tesla pick-up truck, to be revealed next year along with the Tesla Semi truck, will likely have, ahem, the best pick up ever with its own version of Ludicrous mode.