Until the unofficial kickoff of the holiday season on the Friday after Thanksgiving, online-only video game accessories retailer KontrolFreek LLC had a strict policy to never send out more than two e-mails a month.

But, after analyzing the e-mail frequency of larger retailers, the retailer decided to abandon that rule for the holiday push, says Ashish Mistry, CEO of the retailer, which generated $2.25 million in revenue online last year, a 66.7% jump from $1.5 million in 2010.

“We tried to mirror the frequency of e-mails that larger retailers were sending to determine how often our existing customers wanted to hear from us,” he says. That led the retailer to send out seven e-mail blasts between the day after Thanksgiving, also known as Black Friday, and Christmas Day. The increased frequency had minimal impact on the retailer’s unsubscribe rate, Mistry says, and it played a key role in helping the retailer generate roughly $562,000 in sales during the holiday period.

KontrolFreek, which sells online at KontrolFreek.com, wasn’t alone in increasing the frequency of its e-mails during the holiday season. According to a study by e-mail service provider Responsys Inc., retailers sent 26% more marketing e-mails during the holidays than they did during the same period in 2010.

KontrolFreek experimented with a variety of different offers in its e-mails, ranging from a 40% discount offer available for a four-hour period to a $5 off coupon code. It found that percentage-off discounts performed best.

“You have to be able to move quickly, test, learn and adjust,” says Sean Cook, CEO of ShopVisible, which is KontrolFreek’s e-commerce platform provider.

To continue on its growth curve, KontrolFreek is building on what it learned during the holidays in its planning for the 2012 holiday season. “We don’t want to forget what happened last year,” Mistry says. “We’re going to lay out the groundwork for the season now and then we’ll update that plan during the summer.”