Warner worked three years in the Terran Dominion's Special Research Operations branch as a counter-biological engineer. As such, he had a in depth knowledge of zerg biology and tactics. He later joined with Bill "Pearly" Bousquette to join his SceeVee Corps against the Dominion.
On their operation on Gurdlac, Dave was the first to identify that they had hit a zerg tripwire, where the zerg would leave forces behind on rich mineral deposits to ambush anyone who would try to mine them. His insight into zergling biology also helped when he told his squadmates that zerglings could climb nearly vertical surfaces, but only nearly. This allowed them to sheer the cliffs just sharp enough for the zerglings to be unable to climb them when SceeVee Corps laid a trap for them in the canyons.
Bogdanove, Kal-El. "The Fightin' SceeVees." (May 30, 2013). Blizzard Entertainment. StarCraft Lore: The Fightin' SceeVees Accessed 2013-05-30