Advice on Controller Vibration

I have a couple of questions:

1) Is it acceptable to use "pulsed" effects by calling GamePad.SetVibration() every Update() to change slightly change the motor settings, creating the feeling of "punches."

2) Can that pulsing include complete stops of the vibration?

3) Is there any guidance on maximum suggested duty cycles for using the vibration? (Not that I plan to leave it on much, but should I be intentionally limiting the duty cycle if the player engages in non-game behavior like punching all the time for 10 minutes?)

4) Is there any guidance on minimum period of on-off-on cycles?

Basically I want to know if:

a) I can hurt this thing by not following some rules I don't know about, or,
b) The API is watching my back and not passing on dangerous commands to hardware / applying some kind of low-pass filter, or,
c) The hardware can handle whatever this API can throw at it.

Thanks in advance for any advice on these issues.

[1179 byte] By [DouglasMcClean] at [2007-12-24]