It has already been discussed above about the hypercorrection. I just wanted to add that my 4th year Russian professor, when describing the word зря, "in vain," made a big deal about how useful an expression it was, and kept on saying consistantly how it meant "in wain," which I had a very hard time not laughing at. I felt really bad, too--he was the sweetest man alive, but "in wain" was very comical, especially when he kept repeating it for emphasis.

So, yes, what Chekhov does is possible, although his accent is not by any means really Russian. (He is one of my favorite characters, however. Classic trek represent!)