Hmmm, that reminds me of an incident I had a month after a transmission service. I don't know how long it had been going on, but one day I noticed "steam" coming from under my car and realized my tranny was leaking. I took a closer look and also noticed that the transmission pan (that squarish part) had sprayed a fine mist of ATF on my undercarriage. I automatically assumed my tranny was leaking, so I took my car to another M-B shop for them to have a look. They diagnosed the "seepage" as the result of the tranny pan screws not being screwed on tightly. Other than that, they said my ATF level was fine and sent me on my merry way free of charge. But I was pissed at the shop that did my ATF service. I've stopped going to that shop; it seems like they half-ass everything they do!
Anyhow, your post started to make me think and worry a bit. Was my tranny overfilled? The second shop said NO and stated that my ATF level was fine. They tightened the screws and there has been no leaks ever since. I'm just baffled by how someone could have not tightened a screw, or if it is even possible for tranny screws to come loose after a while if they are not tightened tight enough. By the way, car runs fine, tranny shifts fine, and fluid looks clean last time I checked, which was about a week or two ago. I guess I'm just concerned about what you said and the possibility of long-term effects as a result of overfilling, if that was the case.