The Italian turned his back on his trusted 3-4-3 set-up with both sides level, wing-back Victor Moses being replaced by midfielder Cesc Fabregas with 20 minutes remaining as Conte switched to a back four.
The gamble paid dividends as Gary Cahill scored a winner three minutes from time at the bet365 Stadium to send the Blues 13 points clear at the top of the Premier League ahead of Tottenham Hotspur, Manchester City and Liverpool playing on Sunday.
"It's not the first time - it happened also against Burnley," Conte told Sky Sports News. "During the game, when you want to take more risks, when you want to try and take three points and not only one, you try to change.
"But, when you change, for sure there is a greater possibility to score the goal but also to concede a goal. You must know this and then sometimes I prefer to decide to risk it to try to take three points. In other situations I prefer to keep the result."
Chelsea need 21 more points from their next 10 games to be mathematically certain of the title.