Nah, youve just got to show 2 land aways. I was going to put the distance in my logbook but I forgot, nobody said anything so ether they measured the route or more likly took my word for it.
When you fill in your CPL/IR application form you just need to put in the date you did it and they will check the relevent entrys in your log.
I flew coast to coast in Florida and then down to the Keys.
