Yes, as far as I understood "tcp_nodelay on" is more reasonable for the modern web, the whole delay business of TCP was reasonable for terminals.

As the latter part of article describes "tcp_nodelay on" is at the odds with "tcp_nopush on" as they are mutually exclusive, but nginx has special behavior that if you have "sendfile on", it uses "tcp nopush" for everything but the last package and then turns nopush off and enables nodelay to avoid 0.2 sec delay.

Yes, since it with it on the functionality remains off until the final (and only partially full) packet. Rather than being delayed by 200ms, tcp_nodelay sends it out instantly.