Take away the ability to change font color based on thread prefix

This isn't major, but I have noticed many instances where new members change the color of their fonts, since they don't realize that different forum skins may make it hard for others to read their post. This can be solved by just editing the post, but, if it is not hard to implement, it can be avoided in the first place. What I suggest is taking away the ability to change font colors from threads where it is not necessary. By 'necessary', I mean where there is no reason to use it. This would still allow threads with the prefix 'Tutorial' and 'News', etc, to use it, as people often change the color of headers for certain sections of their post.