PLT ENCOUNTERS WAKE TURB CAUSING UNCTLED ROLL OF 30-40 DEGS BEFORE EXITING THE ADVERSE ENVIRONMENT AND REGAINING CTL. THE RPTR QUESTIONS THE MERIT OF REPEATEDLY TELLING THE PLT CAUTION WAKE TURB WHILE BEING VECTORED IN IMC.

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WHILE BEING VECTORED FOR THE ILS 4R; BEHIND A B757; WE ENCOUNTERED ITS WAKE TURB. THIS CAUSED A STRONG ROLLING MOMENT TO THE R. FULL L AILERON ARRESTED THE ROLL AT APPROX 30-40 DEG BANK AS WE CLBED OUT OF THE WAKE. 4 DAYS A WK; 52 WKS A YR; WE FLY INTO BOS. THE MAJORITY OF THE TIME WE ARE FOLLOWING A B757; B767; DC-8; ETC. EVERY TIME ATC ISSUES A WAKE TURB ADVISORY. THIS ADVISORY (GIVEN SEVERAL TIMES) USES UP VALUABLE COM TIME AND DOES NOT INCREASE SAFETY; ESPECIALLY IN IMC! THIS ADVISORY IS NOT A SOLUTION TO A DANGEROUS PROB. AS PLTS; HOW ARE WE SUPPOSED TO AVOID WAKE TURB WHILE BEING VECTORED FOR AN APCH IN IMC? ATC AND THE FAA NEED TO BE MADE AWARE THAT THE WAKE TURB ADVISORY IS NOT A SOLUTION TO THE PROB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR THINKS THAT THE ADVISORY PROGRAM IS DOING LITTLE MORE THAN CAUSING FREQ CONGESTION. WHAT WE SHOULD BE DOING; HE SAYS; IS ROUTINELY SPACING LIGHTER ACFT AT LEAST 5 NM BEHIND THE HVYS ON APCH AND STAGGERING THE PATTERN ALTS; WITH THE HVYS LOWER. IN THIS ENCOUNTER THE FLC HAD FULL LOCK ON THE AILERONS AND THE ACFT STILL ROLLED R 30-40 DEGS. HE SAID THAT THE 10 DEG PITCH-UP HELPED THEM TO RECOVER.