S2UL and Power button

[mobidutch]

I'm trying to figure out what the value add is of S2UL. Right now, the only time I get the S2UL screen is after the phone goes into sleep mode and I have to press the power button to wake it back up.

Well..I am not worried about accidentally pressing the power button, so in that case I have no use for S2UL.

But instead of having to press the power button, is there a way to wake up the phone by simply pressing:
- one of the hard buttons, like the center/OK button
- or by simply tapping the screen

And then use S2UL to actually unlock the phone?