It seems to me that the bleeder screws would most likely never freeze in the caliper if when changing pads it was turned 3/4 of turn.

From my experience bleeder screws break from never being used, over tightened or both.

Haasman

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'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)