MB has gone to great lengths highlighting the many contradictions of vocal mass immigration booster, Professor Peter McDonald (for example here and here).
To cut a long story short, Peter McDonald co-authored a parliamentary research paper in October 1999, which concluded that it is “demographic nonsense to believe that immigration can help to keep our population young”, claimed that “levels of annual net migration above 80 000 become increasingly ineffective and inefficient in the retardation of ageing”, while also recommending “a population of 24-25 million within 50 years”.
“Those who wish to argue for a higher level of immigration must base their argument on the benefits of a larger population, not upon the illusory ‘younging power’ of high immigration”, Mc Donald wrote in 1999