From the in game "Emotes, Checks and Commands"
"@mark use this command to leave behind a marking for other players to examine........Please do not use this command to leave OOC remarks or place things that would require any special equipment or remedies, but have an atmospheric and descriptive purpose only"
The use of ooc explanations at the end of an @mark description claiming the remover will be cursed, placing @mark to describe things which aren't there such as a paragraph describing a dead garda in the road when there is no body, or an elaborate sacrificial scene where there is nothing present but the @mark (no bodies, no placed items, nothing else but the @mark), mists trailing to a certain direction where none are present, I would consider as clearly falling under 'abuse'. That isn't my opinion, that is based on the in game statement as to use of @mark.
Placing a half dozen or more @marks which all say the same thing on one map, is a bit more grey and might fall under the realm of personal opinion. So, I personally think it adds to lag and overkill when thrown about with a macro text to create the same mark on every available surface. This is from some one who has loved the coal marks saying cellar dwellers, but when I see ten of those in an area that I can rotate my camera and hit tab.....again I consider that less atmospheric and more akin to pissing on every available surface to make a mark.
Also there's no way to send anyone an in game tell because there's no way to tell who did anything, as stated above, pcs stand about, then walk off and suddenly there's an @mark that wasn't even rp'd or emoted out ic. It simply appears.
The note making capability hasn't ever seen anything remotely approaching this level of misuse, I sort of attribute that to the effort required to buy a quill and write up a note. If you do all that a player tends to be pretty serious about their message, they had to pay for paper, consider what they were writing and why.
Perhaps the sheer ease of @mark and the ability of using a command in macro means that @mark gets tossed about far more often and that many are done in a less than atmosphere enhancing manner.
Also, I do brush a lot of marks away ic, when the marks can actually be treated as ic. In the cases of "this ams tree" it wasn't even ic because there was no description, no explanation, no atmosphere, so I felt no need to rp anything out.