Are you willing to alienate people who disagree with your opinion? Sure, not everyone who disagrees with you will unsubscribe. But if you can’t take the risk of alienating a large portion of them, it’s better to avoid the topic. The only exception are friendly disagreements. For example, it can be a good idea to show your support for a specific sport team, even if you know many in your audience like another team. As long as they don’t take the sport very seriously, it can be just a fun thing to talk about. I could, for example, tell that I’m more of a dog person (we have two dogs) than a cat person. I have nothing against cats, but I like walking with dogs. I doubt almost any cat person will hold that against me.
Part of the problem is that people are confused about the difference between ‘strategy' and ‘tactics'. It's essential not to get these two confused. They are related – tactics are a vital part of what makes a strategy work – but they’re not the "be all and end all." Too many people neglect a full and comprehensive strategy in favour of a bunch of loosely-connected tactics. So, to recap:
Edit. Even editors need editors. When you're working on your publishing calendar, leave plenty of time for the editing and revision process. Once you send a campaign, it goes straight to the inbox, and you can't go back and update it. Newsletters contain meaningful content, and sloppy ones reflect poorly on the companies who send them. Grammar and style are just as important for email as they are for websites and blogs.

You split your email subscriber list into “cold” vs. “warm” leads so you can compare similar groups of customers in this test. You prepare two versions of your email—one with the normal subject line, and one with a much shorter, punchier subject line. You send half of your cold leads the normal subject line and half of your cold leads get the new, exciting subject line. You also send half of your warm leads the normal subject line, and the other half get the new subject line.
Technology has a significant impact on consumers’ expectations, and those expectations impact how subscribers engage with your email marketing. Brands need to continually demonstrate that they know their customer, which can make it a challenge to stay on top of the evolving context of marketing. An email strategy can make all the difference between building a relationship with your customers and sinking without trace.