This is an interesting question. My understanding is that currently no peated malt is used at Bushmills. I have seen ads for Bushmills in which it was stated that a distinguishing characteristic of Bushmills, e.g. Black Bush, from Scotch whiskies is Bushmills does not use peated malt. Unless I misinterpreted those ads and other sources I've read over the years (and I stand to be corrected if wrong), Bushmills uses only unpeated malt to make its malt whiskey. Why then that reference on the web site you mentioned? Because, I think, in Jackson's World Guide To Whisky from 1987 he states Bushmills uses lightly peated malt. So at that time at any rate it must have, but I think the practice must have changed after. I agree that sometimes Black Bush (in particular) seems to have a smoky hint but I have assumed it comes from other factors, such as the temperature the malt is kilned it, or other production factors.