This demo sort of shows how you can do literally anything if your opponent doesn't attack you. Zer0 for some reason decides to reclaim his shipyard and go mass sonars, with no defence except a couple of subs.
This leaves him absolutely wide open for 5 minutes while Russian has 6 or 8 pelicans. Russian does end up taking out all the sonars but he doesn't press home the advantage at all. Instead he decides to go Big Bertha.
In fairness to Russian he's unlucky that Zer0 gets his shit together and does some magnificent roach bombing. But on this map he either really needs to do more scouting, or get his feet wet earlier.