I was, and continue to be, under the impression that this kind of attack is not possible when an access point has node isolation (a very common feature that even my MiFi router supports, despite it often being turned off in home and even office environments), yet the aforementioned protocol-level DHCP DoS I described would work on any device that implemented the DHCP specification. I therefore fail to see how ARP spoofing is relevant. Remember: we are discussing whether it is a fair belief that any reasonable implementation of DHCP would have implemented the spec as stated.