My little holiday is over. All I have time for is... I don't think you read much of my posts. The analysis at constant velocity would be 'fit for purpose' if you had any interest in the principles involved. The support comes from the experimental results. See (for example) http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/muonex.html#c2 . I think you underestimate me. I have in the past been through every step of the experiment from counting to velocity measurement. Unfortunately those posts have been lost - I don't think my time would be well spent on this occasion if I were to collect up that information again. It is there for you to find if you want to. No comment.