How are you going to bend something and keep it Parallel? I see your point, but this isn't a drag engine...
That's exactly the reason they NEED TO be parallel. The gap you set it to is the narrowest part, so if they're not parallel, as soon as that smaller part erodes, your gap will increase in size very quickly. If this were drag racing, the plugs wouldn't have to last as long, so it wouldn't be that big of a deal. Also, he'd be using narrow center electrodes, so the effect of an angled ground electrode would be minimized.
You keep them parallel by using the bending tool properly. Bend the ground electrode outward with the fulcrum end of the tool near the base (where the electrode is attached to the shell). THEN use the tool to bend the end down toward the center electrode, this time using the tool to ONLY bend the business end of the ground electrode (somewhere around two or three millimeters from the end is good). You should be able to eyeball it and get within 0.010-inch or so, then use hand pressure against a countertop to get it to specification.
Motorcraft has consolidated their part numbers to the point it's difficult to get the right plug for the application sometimes. Champion is the only manufacturer I know of that hasn't taken this retarded route. Autolite tries, but their numbering scheme is so f*cked up, you need the damn .pdf in front of you to make an informed decision. With Champion, you immediately know from the part number what the plug is gonna look like and do.