I guess you can call me magic Dan,
because those plugs have 78,000 on them. Driven about 90% highway, 100 miles a day in extreme MA weather, 0-100 degree outside temps.
What do you mean by "abusing engine maintenance that badly"??? Most platinum plugs last 100,000 miles without problems, yes they are not great for racing, where plugs are changed every time, but last time I looked my 300SE is not a race car. Also why did you state I use more than a quart of oil every 1000 miles? Did the plugs show you that?
1969 RS/SS Camaro Conv. L-89 Alum. Head 396 375HP 4-spd
1987 GNX #419, 2002 RX300
FS: 1934 Ford Street Rod, Blown 383 $48,500 Firm