"a written order was issued commanding that French troops be embarked in equal numbers with the British. In practice this was not carried out."

Well the figures supplied by Keith A of Hertford show that they were not too shy of the mark

198,229 British Troops rescued along with 139,997 French and other nationals, and I do not suppose that circumstances in Dukirk and along the evacuation beaches were such that immaculate firness and order could prevail in the midst of bombing attacks and straffing runs by German aircraft. I would also tend to think that for the average French squaddie inside that perimeter that he would be most concerned with getting home to look after family and loved ones as opposed to escaping to England to continue the fight.

Les from Hull also makes a good point regarding the inshore ferrying operations from beach to the larger vessels lying offshore, they would be noted as having been rescued by the larger ship, it was after all a rescue mission not a competition. The smaller boats would only be "credited" with the soldiers brought back on the final trips, after all no point in them returning empty.

The book you refer us to InOBU would appear to be biased in outlook and very poorly researched. Probably written with controversy in mind to cynically create a publicity bubble to promote sales.