PDC CONFUSION EXPOSES FLC TO DEV FROM CLRED DEP PROC.

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SCHEDULED ACR PAX FLT FROM BOS TO ORD. FILED RTE: BOS MHT SYR.... PREDEP: 'FILED RTE: BOS MHT SYR....' 'REVISED SEGMENT: NONE.' 'REMARKS: MAINTAIN 5000 FT; EXPECT REQUESTED ALT 10 MINS AFTER TKOF; DEP FREQ 133.0; WYLYY 1 DEP; CONTACT 121.65 WHEN READY TO PUSH.' WE ANTICIPATED RECEIVING THE 'LOGAN 2' DEP (VECTOR); AND IN REVIEWING THE PDC RECEIVED BY ACARS; WE NOTED NO 'REVISED SEGMENT;' BUT MISSED THE WYLYY 1 DEP IN THE 'REMARKS' SEGMENT. THE GND TRACKS OF THE 2 DEPS ARE NEARLY IDENTICAL. THE WYLYY 1 DOES IMPOSE ADDITIONAL ALT AND AIRSPD CONSTRAINTS; WHICH DID NOT PLAY A PART IN THIS EVENT; AND NORMALLY WOULD NOT. SHORTLY AFTER TKOF; TWR SWITCHED US OVER TO DEP CTL. UPON INITIAL CONTACT WITH DEP; WE WERE CLRED DIRECT TO WYLYY AND 5000 FT. I REPLIED THAT WE WOULD HAVE TO ENTER IT INTO THE FMS. HE THEN JUST GAVE US A HDG TO WYLYY AND ASKED IF WE HAD BEEN CLRED VIA THE WYLYY 1. I TOLD HIM THAT I THOUGHT NOT; BUT THAT WE WOULD CHK AND GET BACK TO HIM. HE STATED THAT IT PRESENTED NO PROB; BUT THAT THEY WERE HAVING PROBS IN GENERAL WITH DEP CLRNCS WITH RWY 27 TKOFS AND WANTED TO KNOW ABOUT OUR PDC. ONCE CLEANED UP AND CLRED TO MHT; I TOLD THE DEP CTLR THAT WE HAD OVERLOOKED THE WYLYY 1 CLRNC IN THE 'REMARKS' SECTION OF THE PDC; BUT ALSO NOTED THAT THE 'REVISED SEGMENT' SECTION INDICATED NO REVISION TO THE FILED RTE. HE THEN SWITCHED US TO ZBW. WHILE PROCEEDING DIRECT TO MHT; USING LNAV/FMS NAV GUIDANCE; AT ABOUT 15000 FT AND 300 KIAS; THE FMS COMMANDED ABOUT A 90 DEG TURN TO TRANSITION TO THE DIRECT RTE FROM MHT TO SYR. SHORTLY AFTER BEGINNING THE TURN; CTR ASKED IF WE WERE OVER MHT YET. WE REPLIED THAT WE WERE USING NORMAL FMS GUIDANCE TO ACCOMPLISH THE TURN AT MHT; BUT THAT GUIDANCE WAS TAKING US ABOUT 6 NM SW OF MHT. HE THEN STATED THAT OUR TURN SHORT OF MHT WAS REDUCING HIS DESIRED SEPARATION ON AN ACFT AHEAD OF US. WE SHALLOWED OUT THE TURN AND NO CONFLICT OCCURRED. 2 PROB AREAS ARE HIGHLIGHTED IN THIS RPT. 1) WE MISSED THE WYLYY SID IN THE 'REMARKS' SECTION OF THE PDC; IN PART BECAUSE NO REVISION WAS INDICATED IN THE 'REVISED SEGMENT' SECTION. THERE SEEMS TO BE A LACK OF STANDARDIZATION IN THIS AREA. AT SOME ARPTS; AN INSERTED SID IS IDENTED AS A 'REVISED SEGMENT.' AT OTHERS; IT IS INCLUDED AS A 'REMARK.' I RECOMMEND THAT SIDS BE POSTED AS A REVISION RATHER THAN A REMARK WHEN NOT PART OF THE FILED RTE. 2) THE LNAV/FMS TURN GUIDANCE FOR A MAJOR COURSE CHANGE AT HIGH SPD IN THE A320 IS NOT PROGRAMMED TO PROPERLY KEEP THE AIRPLANE WITHIN FAR DEFINED RTE WIDTH TOLERANCE. I RECOMMEND THAT RAW DATA GUIDANCE BE USED FOR ANY COURSE CHANGE GREATER THAN 45-60 DEGS. I FURTHER RECOMMEND THAT FMS PROGRAMMING LOGIC BE MODIFIED TO PROVIDE PROPER GUIDANCE FOR THIS TYPE OF MANEUVERING TO ASSURE COMPLIANCE WITH AIR RTE CONSTRAINTS.