The fact that it's such a clean absence is proof of the grease fill - only a liquid could fill a die so perfectly flush. The pressure of striking the first coin after the grease appeared forced any excess grease from the area. It could possibly have stayed in place for a run of quite a few coins.
The best thing about a bicycle is that it uses no gasoline, therefore the chance of fiery death is greatly reduced.
First Catman, then Gary Burke and now Bigg Fredd - there's one heck of a coin club in Heaven.Our members sell on eBay!