I even started installing it in my parent's computers (not advanced users), reducing to 0 the amount of time I had to intervene to fix their computers. The trick is to configure it in blacklist mode, instead of whitelist. This way it only blocks requests from domains in the blacklist and frame elements. Just with this change you get non-power users out of trouble in their surfing habits and impacts negligibly their use.
I have taught them that if a web is blocked or doesn't work properly is most likely not a web they want to use but that there is also the possibility to turn it off using the on/off button (that they should use very judiciously). In this mode it is not too different from setting up Hosts file but they can understand better what's going on and how to turn it off if needed.
EDIT: fixed typos