COMMUTER CAPT QUESTIONS HIS CIRCLING APCH INTO ACV; CA.

Narrative

THE FLT WAS FROM PORTLAND; OR; TO ARCATA; CA. THE WX WAS 900 OVCST AND 10 MI AT ACV WITH LIGHT WINDS FAVORING RWY 20. WE ELECTED TO FLY THE VOR/DME RWY 14 APCH SINCE WE WERE ARRIVING FROM THE N. RWY 14/32 WAS CLOSED FOR REPAVING; SO WE PLANNED TO CIRCLE TO RWY 20 WITH A R BASE ENTRY (WHICH IS THE NORMAL TFC PATTERN ENTRY FOR THAT RWY). THE PROB LIES IN THE FACT THAT THERE IS A NOTE ON THE CIRCLING MINIMUMS THAT SAYS CIRCLING TO THE E OF RWY 14/32 IS NOT AUTHORIZED. THE CAPT AND I TOOK THAT TO MEAN NO CIRCLING E OF THE ARPT; LIKE FOR A R DOWNWIND TO RWY 32 OR RWY 02. WE THOUGHT A SIMPLE R BASE TO RWY 20 WOULD BE ACCEPTABLE. WE BROKE OUT; AND WE FOUND OURSELVES IN A GOOD POS TO LAND WITH A STABILIZED APCH -- NO PROB. HOWEVER; AFTER LNDG; OUR COMPETITOR CAME ON OVER THE COMPANY RADIO AND WARNED US THAT THEY HAD BEEN GETTING IN TROUBLE FOR CIRCLING TO RWY 20. (I SHOULD MENTION THAT ACV IS A NEW DEST FOR US; SO WE DON'T HAVE A LOT OF EXPERIENCE WITH THAT ARPT.) MY CONTENTION IS THAT CIRCLING INSTRUCTIONS SHOULD BE MORE EXPLICIT IN DEFINING AREAS THAT SHOULD NOT BE CIRCLED TO. ON THE CHARTS FOR CALGARY (YYC); THERE IS AN ARPT DIAGRAM BY THE CIRCLING MINIMUMS THAT CLRLY SHOWS WHERE AN ACFT SHOULD NOT BE. WHY CAN'T THAT DEPICTION BE ON ALL CHARTS? I STILL HAVE NOT FOUND OUT WHETHER OUR APCH WAS LEGAL. MY POLL OF OUR PLTS IS ABOUT SPLIT 50/50. WHAT DO YOU THINK?