I think "hiding" the SSID is a particularly stupid advise. The access point will still send the beacon frames, just with an empty SSID, so the network will show up as "hidden network", or similar, drawing more attention. In the end, it doesn't even matter because those that know how to crack a network with a weak password will also know how to recover the SSID from the clients, which is trivial.

Even worse, since the clients can't see the presence of the known network, the only way they have to connect is to continuously probe for the network (this is what reveals the SSID). Besides draining the battery faster, it's a massive privacy concern: imagine walking around with a megaphone announcing all the places you recently have been.