In Pool v. Bell, 209 Conn. 536, 541, 551 A.2d 1254 (1989) the Court squarely addressed situations in which a physician in one specialty is called to testify as to the professional standard of care applicable to another specialty. "The witness must demonstrate a knowledge acquired from experience or study of the standards of the specialty of the defendant physician sufficient to enable him to give an expert opinion as to the conformity of the defendant's conduct to those particular standards, and not to the standards of the witness' particular specialty if it differs from that of the defendant. . . . Without ruling on the correctness of the 'overlap' standard . . . the crucial question is whether . . . the expert knows what . . . the standards of practice are." Id.