In which case, why is this not a subtle form of anti-Semitism?

Language may also introduce a more subtle form of bias.

After a year, you're almost always talking about some other subtle form of sudden death.

But the more subtle forms of the practice were in wide use anyway.

"This can be a subtle and effective form of marketing."

But over the years, as I passed from one level to another, a subtle form of communication began to take place.

But how did such a subtle form of protection evolve?

A subtle but insidious form of mind control is at work.

You might call it a subtle form of political patronage.

Right now it still exists, maybe in just a little more subtle form.