SEX – Breakfast of Email Engagement Champions

Waiting in my inbox a few days ago was my latest email from This one had a particularly startling subject line:

“SEX CEREAL: Fuel your fire – Firebox UK Exclusive”

Now, my followers will know that Firebox is one of my favourite brands, and I have written about them before (see Figaro Digital and NetImperative). For those unfamiliar with this brand, they are an online gadget shop, and their emails have a fine tradition of risqué humour and tongue-in-cheek innuendo.

However, this example was a bit OTT even by their standards! And as far as subject lines go, it subverts pretty much every best practice known to the email universe – block capitals, references to sex, spam triggers words like “exclusive” – they’re all there!

Sex Cereal - Fuel Your Fire - Firebox UK Exclusive

So naturally, I started wondering how this particular campaign performed (so to speak!). I loaded up the sender into Return Path’s Inbox Insight competitor intelligence solution and the results were intriguing:

Firebox Engagement Metrics: Sex Cereal

Measured against Firebox’s 30-day benchmark, we can see that Read Rates for this email were actually slightly better than normal. The fact that “Deleted Unread” rates were almost 1/6 higher suggests that it wasn’t everyone’s cup of tea, but the “ISP Spam” rate was around 1/5 less, suggesting overall subscriber engagement was positive. This is reinforced by the fact that not a single spam complaint was generated from the subscriber panel.

But what about the risk posed by message filtering? Solutions such as Spam Assassin have rules such as “SUBJECT_SEXUAL” and “SUBJ_ALL_CAPS” so aren’t these factors likely to be problematic? To answer this question, I submitted a copy of the Firebox email creative to Return Path’s Inbox Preview rendering & content assessment module. Intriguingly, this email scored a 100% pass rate – green lights across the board, even for some of the more notorious filters that we test (like Postini!).

So this would appear to prove what we’ve known all along – email content is definitely not the deliverability influencer that it once was. However, the converse is that approaches like this one should not be over-used, or they start to lose effectiveness. Firebox provides a good illustration of this – following a website revamp in mid-March, emails are now sent on a roughly weekly basis with subject lines that start with “NEW STUFF”:

Firebox Engagement Metrics: New Stuff

Comparing the effectiveness of this approach during the first 45 day period versus the subsequent 45 days, it can be seen that average Read Rates for these emails have reduced while average ISP Spam Rates have increased by 1/3 – subscriber engagement has clearly declined as the novelty value has worn off.

What are the key take-outs from this exercise?

  • It is important to know your audience when using an approach that is outside of the norm. It is likely that subscriber engagement will be amplified – but negatively as well as positively.
  • As Return Path has been advocating for some time now, sender reputation and subscriber engagement metrics influence deliverability to a substantially greater extent than content.
  • This means that some email marketing taboos such as the use of block capitals and “spam trigger” words can be deconstructed – provided that they are used in a sensible fashion to maintain impact.
  • Members of Return Path’s Certification program benefit to an even greater extent as some spam filters will apply more relaxed treatment to these emails.

So get testing, and give your email program a lift. Breakfast will never be the same again!

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