I've been at my job for 8 years and never have I noticed skid marks in the toilet. It's a relatively small office and although I don't like sharing the bathroom with other folks, people here tend to be somewhat clean and non-offensive... until you came. We hired you three months ago and that is exactly the timeline I started to notice brown smudge marks in the toilet. It's disgusting!
I also always hear you eating in your cubicle because for some reason you think munching on pretzels all day is totally fine in a quiet office. Crunch, crunch... bag noise... crunch, crunch... bag noise... how on earth you don't realize that the entire office can hear you is beyond me.
I'm not saying the pretzels cause your loose stools, but something in your diet does. And who doesn't look in the toilet after they've flushed? I assume you have to see the brown smearing you leave behind and it is therefore a conscious thing... perhaps like a dog marking its territory kind of thing?
Regardless, it's fucking gross and thank you for possibly making the next 12 years before I retire a living hell.