Unless you’ve taken a vow of pop culture abstinence, you’ve probably seen or at least heard of the amazing vocal performance given by one Susan Boyle on Britain’s Got Talent (an overseas show similar to American Idol).

If you haven’t seen the video clip, I urge you to watch the performance, and – perhaps more importantly – the reaction of the judges and audience.

Susan Boyle is not your average wannabe performing artist. She is a stocky, unemployed, 47 year-old, never-been-kissed woman who lives in a small Scottish village with her cat, Pebbles. Despite the obvious handicaps presented by her lack of exposure and atypical physical appearance – unruly gray hair, obscenely thick eyebrows, a double chin, and a matronly dress – Susan’s pre-audition interview was full of cheerful enthusiasm and understated intention. She confidently told the co-hosts that she was going to “make that audience rock.”

And, she did.

Turning snickers into smiles

When Susan Boyle let loose the opening notes of “I Dream a Dream” from Les Miserables, every snarky, condescending member of that audience fell into a stunned silence. Within moments, the entire place was on its feet cheering wildly as Ms. Boyle powered through her passionate and beautiful performance.

After I mused about how each of us yearns to do something amazing, and then about how shameful it is that an entire audience (a world, even) doubted this woman’s singing ability based purely on her appearance, my thoughts turned to more practical observations. There is a very important marketing lesson to be learned from the amazing Susan Boyle.

Under promise and over deliver

When I’m wearing my project manager hat, I often counsel clients to “under promise and over deliver.” As a writer, I recommend the same strategy. Although you want your marketing copy to sell people on the superiority of your solution, you need to be careful about making misleading statements. Hell hath no fury like a duped and disappointed customer.

Part of Susan’s magic was the delighted surprise of her audience. She stated in no uncertain terms that she was going to “rock” them, but they didn’t actually expect her to do it. I’m not suggesting that you approach your market in a way that diminishes your products and services. I’m suggesting that you vet your copy against the question, “Can we actually deliver on this promise?”

One of the best ways to grow a business is to keep your existing customers happy. Happy customers are loyal customers who will give you great word-of-mouth (WOM) advertising for free. Setting realistic expectations is critical to keeping customers happy. And, when you have the opportunity to do better than you’d promised, you will absolutely rock your audience like Susan Boyle.

The flip side – Ruh-ro …

The flip side of the “Boyle Effect” is the train wreck that took place on American Idol last night. Introduced with all manner of hyperbole, Miley Cyrus took the stage for what was, in my humble opinion, one of the worst performances of the season (and that’s saying something!).

I feel badly for Miley. The ridiculously high expectations created by the press and her own PR team put this young woman in the difficult position of trying to live up to the fanfare that precedes her. She’s her own “tough act to follow.”

If your copy makes promises that your business can’t keep, you’ll find yourself in the same, uncomfortable situation – constantly engaged in damage control and reputation triage.

Do your marketing materials set you up to be a Susan Boyle or a Miley Cyrus? Care to share your war stories?