The way I see it - if you have a forum there is no reason to allow comments on articles that are posted on your website. Wordpress has a comment system built in, this is default and I do not know of a way to fully remove it. All you can really do it turn it off. But if comments are turned off then at the bottom of every article there is a message "comments have been disabled". If you are using Wordpress as a website, or a landing page, the "comments have been disabled" message just looks tacky. Some of the other content management systems such as mambo, drupal, mdpro, postnuke and joomla either have a built in comments system, or have add-ons that allow comments on articles. If you wish to try this on a test site, just follow the instructions I listed for Wordpress, but for what ever CMS you are using. Any forum can be used for this application - it does not have to be SMF. If you like MYBB or VBulletin then use that forum software. I am just using SMF as an example because that is what I used to build this site. What I did, I edited the wordpress page templates and removed the code for the comments. The part that says "comments have been disabled" was also removed. Even if comments were enabled, nothing would show up on the page, because all references were removed from the templates. This also stops those pesky wordpress spam bots dead in their tracks. Write up an article for your website (or landing page) and publish it. Go to the forums and start a thread. I usually provide a link to the article in the thread and state that "this thread is for the discussion of article ABC." Copy the address to the thread. Go back to the article and edit it. On the very last line, put a comment and a link. Most of the time I will say something like - "If you wish to comment on this article, then visit this thread in the forums." So the thread and the article are linked together. Edit the wordpress and smf themes so they look as close alike as possible. But a lot of times they will not look exact. Example: Wordpress webpage - http://www.fortresstraining.com/ SMF forum - http://www.fortresstraining.com/forum/ In my opinion, using SMF for your commenting system is a lot better then using the wordpress commenting system. People can post images and videos a lot easier in SMF, as compared to the wordpress comments. On my smf forum I have an automatic video embedding modification installed. So members can post youtube videos straight to threads. If members are discussing an article, its possible for a member to make a video and post it to the forum thread, where that is not possible with the wordpress comments system. Because there is no way for members to comment on the articles directly, there is no reason for them to log into wordpress. So there is no need for a bridge between smf and wordpress. Bridges can sometimes break things when you upgrade one side or the other, so not having a bridge fixes that problem as well. I have had some bad experiences with bridges and am trying to stay away from them SMF and Wordpress share the same database, so backing up is a one touch operation. SMF is installed as a /forum folder under wordpress. So when I back up the whole site, I just download the entire HTML directory. Wordpress also has some excellent built in Search Engine Optimization features. When these are tweaked, wordpress sites can get some good rankings in google results pages. Wordpress does not take up a lot of server resources, as compared to "other" content management systems. The website I linked to above is the first time I have tried this. Currently I have two more sites waiting for this same exact type of set up. But one of the draw backs, its takes a lot of time to tweak the themes between Wordpress and SMF so they look alike.
I've also disabled Wordpress comments and have completely removed them. Keep in mind that removing the code snippet for the Comments boxes will not remove the comment functionality, or the database table. Spam bots can still inject comments, even though they're invisible. It's annoying, and I'm surprised that Wordpress never made a true way to remove comments entirely.
Big downfall to this is you need a way to convince your readers to register to your forum to comment. Otherwise you're going to have a forum with hundreds of 0 commented posts (depending on your posting frequency), which shows possible members the forum is dead...