Leon Constantine put the Bulls into an early lead in Saturday's League Two clash at the Prostar Stadium but goals from defensive trio Kelvin Langmead, Shane Cansdell-Sherriff and Graham Coughlan - all from set-pieces - secured the points.
Town's next three games are against promotion rivals Bury, Rotherham and Bournemouth, and Simpson said: "The eight days starting next Friday are very important.
"Teams have been promoted from this league having quality from set-pieces and if we can become another one it'll be fantastic for everyone.
"I'll take set-pieces to the end of the season if needs be."
Source: Team Talk
Source: Team Talk