In a Nutshell
Blog commenting can be an integral part of blogging and an essential SEO strategy. But It can also be a waste of time. This article details it from both angles. You can see how installing a blog comment section on your blog has its good and bad sides, and you can see the potential good and bad sides of commenting on other people’s blogs for SEO purposes.
When installing a blog comment section yourself
First let’s focus on the pros and cons of adding a comment section to your blog so as to allow other visitors to comment on the articles.
Comments may show the popularity of your blog to users and search engines
A lot of comments, on your comment section, is a vague indication that your blog is well attended. People are going to be cynical and possibly assume that you wrote the comments yourself with different names, but even a lot of fake comments are going to show that your blog is more attended than if you have no comments at all. The search engines may also take your frequent receipt of comments as a sign that your blog is either well liked or useful (both are search engine friendly concepts).
Your comment section will receive spam
On the down side, your comment section is going to receive spam. If you set up protocols to stop spam (usually with content management system plugins) then you are going to scare a few genuine people off from commenting. Even if you put something simple on your comment section such as a CAPTCHA widget, you are still going to scare away the commenters who cannot be bothered with the widget. Plus, you will never stop manual spammers because they are doing the same things as your regular commenters.
Followed comments may be perceived as updates
Most people put a “no-follow” tag onto their comment section. This helps to slowly dissuade commenters from adding links onto their comments. However, you will miss out on the fact that search engines may perceive comments as updates on your blog. And, regular updates are things that search engines look for when ranking up a website.
Followed comment updates are unlikely to be usable SEO content
If you use the tip mentioned above then the content added is hardly likely to be SEO friendly in any way. This is a bad thing and will nullify the positive effect of frequent updates. There are things you can do to put a stop to this, such as putting your comment section in a H4, H5 or H6 tag so that the search engines read it but do not pay it very much attention.
Comment sections may keep your viewers occupied for longer
Once your blog viewer has finished looking at your blog post, he or she may look at another post (hopefully), but will probably leave your blog. A full complement of comments is going to keep the viewer on your blog for longer, and may even encourage him/her to comment. This is especially true if the viewer sees a comment that engages him/her.
Your comment section will receive trolls
Troll(s) in the online sense is a fairly new word, but it now has its own section on Wikipedia so it is officially part of the zeitgeist. A troll is Internet slang for a person who is purposefully offensive on your blog comment section. It is usually done on purpose to entertain the troll (the person commenting).
They often try to provoke an emotional response or disrupt the usual flow of the conversation. Trolls may go onto a fan site for a TV show and make comments about how crap the show is, or may deface an Internet tribute website in order to cause grief to the family and friends of the deceased. They often post inflammatory comments on comment sections, cause arguments and post off-topic messages for no good reason. So as a warning, if you start a comment section then you will have to delete the occasional troll comment(s).
Adds to the size of the Database
Well, at times you must have noticed that your blog database size keeps increasing although you are not posting anything new or are not installing any plugin. This happens because of the spam comments that are posted on your blogs by other spammers. Although Akismet blocks the comment, a copy of it is stored in it’s cache or the database table. So, it is important that you monitor your wp_comments section quite regularly to remove the worthless comments.
When linking from other blog posts
Now that we have covered some aspects of installing a comments section on your blog, let’s check out the pros and cons of adding comments with links onto other people’s blogs.
You have no control over the fate of your comments
When you post a comment then it is not like posting a guest post or an article. At least with a guest post the blogger is honor bound to keep your post and link going for a while (or longer). And, with an article you can often leave the article and the link on the site for as long as the site or your account lasts. But, with comments and their links you have no control. The blogger could decide to delete your comment/link now or in 10 years.
Comment section links give backlinks without having to write a lot
They are really great for backlinks because you do not have to go to the trouble of writing an article such as you have to with article sites or guest blog posting. Nor do you have to sign up for anything or be all nice to a blogger. The hard part is finding comment sections that are followed (i.e. do not have the no-follow tag), but when you do then you can hop on any time and add a link to your website with very little writing. You just have to hope that the blogger does not delete your comment or link.
Comments do not tend to last as long as guest posts or articles
Just as the previous paragraph states about having no control over the destiny of your comment/link, you will find that links on comment sections do not tend to last as long. When you check your broken backlinks using your SEO tools, you will often find that the comment backlinks are the ones that break sooner rather than later; this is not always the case, but in general it is.
Finding followed comment sections is difficult
So many people have started to add the no-follow tag to their comment sections that it is now very hard to find ones that are followed. Even WordPress have set their comments sections as default no-follow. The WordPress user has to change the settings on his/her WordPress blog in order to make the comment section followed. Few people know about the frequent updates benefit (mentioned earlier in the article), and even the ones that do are just too sick of spam comments to care.
Many blog owners will delete links in their comment section
This is a common practice as the blogger looks through his/her comment section. He/she will see a comment and just delete the link but not the comment. If you want to avoid this then make the link a vital part of the comment.
For example, you have started a discussion about a certain event and the other person says something such as, “It was never caught on camera!” Your reply can be something like, “Yes it was, the video is right here: - ” adding the link after the comment. That way if the comment link is deleted then the comment is invalid. This may convince/push the blogger into not deleting your link. Well, it’s about being a bit clever.
Obviously, if that short comment was your one and only comment, then the blogger may have no qualms with deleting all of your comment because you have added so little to the comment section whilst still adding a link (which is cheeky).