These sorts of issues are exactly why careful consideration is taken by moderators, in consultation, before we take steps. We are not here to censor people. There are often context issues related to individual images. However, we do not want CF to become a "gore" site. We are interested in maintaining the core crux and erotic fantasy emphasis of the forums. That said, in the case of individual images, if those are deleted from time to time, this is not meant as a personal statement about the person who posted the images, but is simply the removal of an image (or sometimes a post with several images) that the moderators have agreed do not fit into the overall context of the forums.
With regard specifically to beheadings, where the beheading is in the context of a story (either a pictorial or as an illustration of a text story), this might be acceptable. However, series of gruesome, graphic beheadings just for the sake of showing these images might be considered gratuitous. Context is often important.
Moderators are not perfect. We try to do our best to maintain the rules and be fair to all CF members. That said, moderator actions, as supported by the forum owner (ImageMaker), are final. We take this responsibility seriously, and we will continue to try to maintain consistency and fairness in our decisions.