totally agree mate, but if it turns out he detected a problem from head test, you then have a reason for removing cam cover...
from what we're told, it was just a visual diag, in which case, your probably right, have come across porous cyl heads before but in this case seems highly unlikely...
all i ask of anyone...dont go slaughtering the mechanic till you have all the facts,
when i get calls like this, its only ever going to end badly,
ill spend as much time as necessary to show/explain what im doing/done, but there comes a point when i just walk away and leave them to sort elsewhere, when the customer refuses to accept what you say/show all because somebody in the pub or www has told them i dont know what im doing even though they have never so much as looked at the motor.
other favourite one is "RAC/AA man said it was this,"
so many people refuse to believe when i tell them they were wrong, god knows why???...couple of times even got to the point where, ok, i'll do what the breakdown says...so long as your prepared to pay the full cost of this unecessary work as well as the cost of fixing the real problem....love the sheepish looks when its done and dusted