I know how you feel... I had a long haired cat many years ago that was very scared of cars, and even a short trip to the vet would regularly result in distressed crying and extremely stinky "accidents" - and as you point out, "unplanned" poops are not solid... Since we was long haired, it had to be a bath as soon as we got home. I felt so sorry for her - first the stress of the car to the point of soiling herself, then the stress of getting a bath! Poor little girl... Eventually I learned she did much better if she sat in my lap (it was Italy and a long time ago, so it was not illegal and she was a very gentle cat); she would lean against my chest and drool all over me while making the crying sounds, but at least she didn't get as scared and she wouldn't have stinky accidents. Since she was also able to drop a ton of fur when stressed out, regardless of the fact that I groomed her every day, I would arrive at the vet completely covered in cat hair and cat drool, a sight to behold...
