he was doing less than the speed limit, as there was a lorry infront anyway.
Ok so some transits can do 115mph, my works ST Transit althought its been remapped could easliy do that dispite carrying a few hundred kg's of tools in the back. However if he was indeed following a lorry in the photo or at that particular time then clearly that ends the debate/child killer blah blah. Stick a copy of the letter your dad got along with an a4 peice of paper simply saying "LOL?" and mail it back, see what happens next.