Yes, the 722.6 is adaptive. It should learn the new driving style on it's own, unsure how long it will take. An aggresive driver and a easy driver on the same car can cause this to happen after switching drivers. Any kids in the family borrowing it? hehe.
The sprak plugs are due at 100K OOORRRRR 4 years (1998 ML owners take note!!!! Many 98's were built in 97 and are overdue, the plugs can and will seize to the head!), also the fuel and air filters at 4 years or 60K!!!
Gilly
(I think I won't correct sprak plugs, sounds cooler somehow
)