When my trans fluid was overfilled and it spit out, it still maintained a less, but still over-filled level following the spit-out.
Also, I believe if you overtighten the pan, you may also crush the gasket and cause a leak...
2003 S500 Black/Charcoal
1990 560SEL 61k Arctic White/Grey
1988 420SEL Black/Palomino Sold @ 85k
1987 420SEL Midnight Blue/Grey
1986 420SEL Diamond Blue/Grey
1983 380SEL Champagne/Palomino