Hey El !
True about the battery vs phone status...I think what they are saying is if its not on you won't answer it/ make a call/ drop it and accidentally dislodge the battery (covering their ass without actually saying leave your mobile at home).
Regarding WI-FI i have a wife and a HI-FI...is this a combination of the two. In other words I have do not have enough theoretical knowledge (and no empirical evidence whatsoever) about WI-FI and would appreciate some enlightenment.
RMC