The subject line stands as a sort of Bucephalus of email marketing.

Before becoming Alexander the Great’s most famous horse, Bucephalus stole breaths while eluding tamers. Enamored like many before him, a 13-year-old Alexander essentially wagered 13 talents — a really colossal sum — on his ability to break Bucephalus.

Picture yourself as Alexander and your subject line as a magnificent horse. Why? Because you want to become the greatest email tactician of all time, starting by breaking a beast that will help you down the road. And when it comes to email, the subject line stands apart from everything else.

Recipients enter an email campaign through the subject line. Not every open is affected by its style, but for opens that are affected, you’re gauging a campaign’s life and death. Clearly, taming the subject line provides a smart marketer with a huge advantage over a blind one. It’s your war horse waiting to happen.

When you approach multivariate (or A/B) testing early on, this email Bucephalus seems perfectly harness-friendly too. Few other variables alter because of an email subject test, so your results are clean, trim and easily decipherable.

But then you hop on.

Quickly, you notice this is a wild beast. Results vary radically week to week and day to day. Stark differences in approach garner identical results. Just as you think you see the most effective format, its effectiveness disappears.

It’s enough to make you jump off and fork over your 13 talents.

Here’s my key piece of advice though: You shouldn’t commit to taming Bucephalus, you should commit to riding Bucephalus.

Instead of breaking the code of email subject lines and lazily setting your campaigns on autopilot, realize one of the key overlooked aspects of A/B testing: You can use it actively. The way to benefit from email subject line testing is to gather data for immediate response, and to implement that as part of every campaign you value highly.

Send “feeler” tests out for those campaigns (A,B), shortly before you plan on sending a final blast (C). Use segments that are large enough to make accurate judgments from but small enough to not steal energy from the eventual product. If “Bucephalus Conquers the Universe” (A) beats “Want a Great Horse?” (B), then send A to C.

Realize that next time, B might win. So do the same test again.

Play around. You don’t have to predict anything, you just have to go where the horse is most comfortable going.

The legend goes that Alexander noticed Bucephalus panicked over its shadow. So the little Great led the horse toward the sun, whispering in its ear. By responding actively to Bucephalus, Alexander was able to claim a thing which would carry him successfully through many battles.

BONUS TIME

Maybe that was a little too abstract for you, and in that case — any case really — here’s a few additional Sun Tzu-style subject line strategies.

• Know the Turf – Your organization’s name already appears as the sender. The date sent already appears as the date received. Don’t waste precious messaging space on elements that have columns already dedicated to them in email programs.
• Establish a Presence – My personal preference is to anchor subjects with a word that very quickly identifies the general purpose for sending. Something like “News:”, “Event:”, “Sale:”. This helps recipients understand the organization of your campaigns and theoretically develops good opening habits among them. If you allow manual segmentation, this also guides your recipients as to which segments they find relevant and prevents them from bulk unsubscribing in frustration.
• Hit the Target, Not the Country – While you may get a higher open rate with a general subject line like “Laugh at These Puppies!”, you’re potentially losing people who will actually convert on your Bucephalus mini-statue sale. Making sure the subject is relevant to the recipients your content is relevant to: crucial.