The riding beyond their limits would have been more of a contributing factor than what those limits actually were. In my limited experience on the DS (I am not quite to 120,000 miles), I find that I can handle twisty bits at well over the posted speed limits with lots left in reserve. However, If you cannot stop - or even apply the brakes - then you are going too fast and will end up hurt or dead.
If you want to compare the width of tyre contact between a standard MC tyre and a DS tyre, then ride through a wet bit of tarmac (parking lot or similar) onto dry tarmac and then lean the bike and make a turn. If you measure the width of the contact patch you will find that the DS is wider.