When writing for SEO, we care as much about breadth as we do about depth. If I run an e-commerce store that only sells t-shirts, it doesn’t mean I can’t have a blog post that talks about jackets that go with them. Content diversity and relevant semantics are important for SEO as a more diverse range of topics discussed means we’re more likely to actually appear for more diverse queries.
This isn’t how SEO works. There’s nothing magic about what an SEO can do to the text in your content to, “SEO” it. Firstly, using SEO as a verb usually indicates that we’re on the wrong path. Secondly, writing content should be about the audience first and foremost. Have your SEO team help select topics and then consider the sub-headings in the context of your brand and the message you want to curate. It’s that’s agreed by both parties it’s very likely any keywords your content needs will be included in your text. If you’re concerned that’s not the case, a tool like Clearscope can help create SEO briefs and keyword insights.