"No, he's right. ALL mechanical switches will spark"
Now, technically, you are right. But in practise if the
spark is bad enough to be visible, there's something
very wrong. I just took off two covers here.
One used relatively new switches, one uses switches
that are ver 25 years old. and then I flicked them
off and on about 10 times each. NO visible spark.
As I expected. Think about it. the swicth itself
is enclosed. For the spark to show it would have
to be gigantic. I stand by my earlier suggestion
that the sparking switches are bad. Maybe this could
be an episode of myth-busters?
....thehick