I get that you aren't directly referring to doping, but the doping allegations rules can be quite hard to implement, so mods just use their own common sense in each individual case.. It's usually a case of better safe than sorry when a post like yours is deleted, since nobody wants the site we all love to get in trouble right?
Many forumers like playing with the doping rule and hinting at it and sometimes hinting at certain players, without actually referring to any athlete by name. Then some of them complain when it gets deleted. which gives us a great big headache either way.
Only the obvious doping allegations get infracted- all others that involve forumers hinting at things are just deleted. The most annoying one to deal with has to be when people spam stuff like "good doctors" in the most obvious way possible .. Jebus, it's like being back at school sometimes.
I actually have wondered for a long time why MTF would get in trouble, since it's literally the only forum I know where it isn't allowed. For example, at TW it's allowed as well while they have a lot more commercial interests to protect than MTF.