The bottom line is this, I'm not sure your suggestion that you're still in line with Mac interface standards holds. You don't have to single click then double click a file to open - that would be a disaster if it were system-wide.
I think you misunderstood my paraphrase of the Macintosh Bible. Their point was that the act of double-clicking represented two actions: selection (accomplished by the first click) and action (accomplished by the second click). I didn't mean to imply that you had to single-click first to select, then double-click to open.
I don't know what the 'new' Macintosh Bible says, but I haven't seen triple clicking in any other application on Mac
Actually, triple-clicking has a function in every Mac program that deals with text: The selection of an entire paragraph. So we're definitely not the first or only program to use it. Where we break with the "standard" interface is that we use it to look things up rather than to select whole paragraphs. We figured triple-clicking wasn't well-known as a selection shortcut, so it wouldn't bother anyone if we replaced it.