There are many situations were you don't need to face experts security plp, you only require to hide your data, and hide you have hidden data. Even when you face experts the possibility to argue between a random formated partition and an encrypted one is an advantage.
Erase software is aware of the situation you described, it writes every sector once than more time, you can set what pastern to write, you can set how many times... So you can force that 1 million of 0s are not written. You can force first all 0s , then all 1s then 01, what ever you want
About recovering magnetic state before formating, ok the problem exist, solutions: 1) you can use a new disk , 2) you can use a previous encrypted data. Both solves the problems, but we are speaking about plausible deniability about current data on the disk, encrypted vs random formated. We don't care about previous data. This topic has more sense on other thread.
About 802.11, you are so, so, wrong. Under strong security environment 802.11 is inviable, broadcast is inviable. All WIFI headers are low protected and they contain critical information about your network (macs, IPs, discovery protocols, etc), some control IP headers or 802.11 headers are low encrypted too and they contain critical information about your network. the IP data fields that contain data about the target encrypted partition are encrypted, but they are broadcast so brute force attacks could take place at peace, you let the attacker to sniff your packets day and night. You never will see a really critical security environment using wifi.