How to keep Yun connected to WIFI

Does this same daemon constantly monitor the status of the wifi during runtime and if it drops reverts back to AD hoc mode.

Yes

does it only run on boot to check for the presence of WIFI

No, It constantly monitor.

It doesnt makes sense to me to put it in the rc.local as if I understand correctly that is only run at startup to start the #wifi-live-or-reset

Yes.

The Wifi Signal level could cause internet drop off, confirm wifi Signal level:

http://forum.arduino.cc/index.php?topic=188101.msg1583665#msg1583665

The Wifi has build in re-connection function, the code is really for back plan.