When I went to college in Boston, most days I'd get off at Copley and walk past Copley Square and admire the 60 story Hancock Tower even though there was nothing but old and historic buildings surrounding it--Trinity Church, Boston Public Library, Copley Plaza Hotel, and the incredible rows of late 19th Century brownstones on Commonwealth and Beacon Avenues. Not once did I ever think that tower, angled so perfectly to the edge of the public square, reflecting the blue sky, clouds, and the church, diminished in some way the area. It was the opposite. Sometimes contrast enhances the beauty of each source. It's not the height of a building, but rather how it's designed, in my opinion. But for the Old Port, if not thought out enough, yes it could become a regretful distraction. They better do it right or don't do it at all.