They are not to be avoided, as they work well (as long as you are near your computer when you want to turn on or reboot your iPad. But - as of right now, there is an untethered jail break for the iPad, so you don't even need a tethered one.
I guess I need to ask - where are you reading about a tethered jail break? Cause there isn't one, currently, for the iPad...
Marilyn