Oliver: Without your car's year... ???
Mine is a 2010. I went out after reading SW17LS' comment and tried again. After about 20 seconds mine goes completly dead. It's saying "Bad LS owner!!". Nanny car.

Mine is a 2010 also. I almost gave up and pulled my finger off the button, when it finally fired. I wish there was a way to reduce that delay time to 0 seconds. I don't want to push the brake pedal.

I just edited my first post to note that the reason my 2010 LS would not start this way was because my car suffered from an Operator Error [the worst kind]. DUH> I went back out- again- and THIS time I remembered to Push the Start Button once to set the computer-and AGAIN & HOLD IT to make it start without holding the brakes. Ouch.

Worked on my 07.

I pressed the start button without applying the brake while the mechanic was working and now when the engine is on, there is no display light on the dashboard

I don't know what to say....

This subject seems ridiculous but it works, catch is you have to have the key somewhere in the car on the 13 and up models. I can't say for the older models but don't see any scenario where this would be helpful with the exception of running off the road in a remote area and having broke your legs and arms then had to push to start with your nose because the car was stalled...even then

Just in case anyone is interested, I can confirm this also works on a hybrid. Tested successfully on my 2008 LS600hL.