pronouns - Sentence: use of is/are with you yourself

Can't seem to figure this one out:

Of course, it is more difficult to analyze those signs if you yourself is/are stressed beyond belief.

Both seem to sound wrong (or maybe I'm overworking). Removing yourself solves it; yet I'd like to still keep the emphasis. As far as I'm concerned, the double pronoun is perfectly fine to use, and also is present in different languages: German "Sie selbst"; Russian "вы сами"; Latvian "jūs paši"; etc.

Answer

It's are.

You goes with are and the emphatic yourself (or yourselves if plural) doesn't change that.

Of course, it is more difficult to analyze those signs if you yourself are stressed beyond belief.