Since I did not make the trip, and now fueled by the photos I've seen, I've been reading a bit about L'Eroica.
Here's a nice article by a British cyclist about his 5+ hour ride over the 80km (50 mile) variant, along with his wife or grilfriend in 2005. Gives a good sense of just how very demanding the course really is. A few more photos, too... note the photo showing the splendid early Peugeot jersey worn by one of the entrants.
http://www.flammerouge.je/
Their elapsed time was at a rate of under 10 mph (16 km/hr)... and that was a considerable challenge!
Bob Hanson, Albuquerque, New Mexico, USA