I tried your credibility link to a blog written by Anonymous ExNokian. AXN has convinced me that TA is being honest. The link complains about three graphs, and has a link promising to tell me what is wrong with the first graph and probably has similar links to the next two graphs, but I never got that far.
The first graph illustrates Elop's promise to convert Nokia's smart phone customers into Winphone customers. TA says his graph is a tidied up version of one from slashgear. AXN points out that TA missed out 'not a prediction' from slashgear's graph, and changed the vertical axis from net sales mix to revenue mix. Both are careless/naughty mistakes, but both graphs clearly represent Elop's promise to convert all of Nokia's smart phone customers into Winphone customers. TA and AXN both have graphs for what really happened.
AXN's graph shows the proportion of smart and dumb phones sold by Nokia. It looks a lot like the original 'not a prediction' graph, and makes it look like the 'not a prediction' graph was an accurate prediction.
TA's graph includes a white region at the top that grows with time. The area represents Nokia's smart customers buying Android/iOS. Elop retained 3 out of 20 smart phone customers.
AXN's graph is at best completely useless for checking Elop's promise to convert all of Nokia's smart phone customers into Winphone customers. What you need is something like TA's graph. Of course AXN disagrees with TA's numbers, and promises to explain in a link to another of his posts. I got part of the way through that, and found more rants, and promises to substantiate them in other articles.
Where AXN does have numbers, they are numbers shipped, not numbers sold and they are often for only one region and not the whole world. Personally, I disagree with TA's assumption that the difference between 'units shipped' and 'units activated' represents unsold Lumia's in boxes with the retailers. I always thought Lumias were shipped out, shipped back and shipped to the region where Microsoft wanted to quote a large number of units shipped (opinion - no evidence).
I would agree that TA rabidly despises Elop, and by association, does not like Microsoft at all. Where did this hatred come from? TA makes it quite clear that he is unhappy about Nokia's loss of profits, loss of unit sales and loss of market share, all of which happened while Elop was in charge. TA places almost all of the blame on Elop (Ballmer gets a some blame too). Given TA's feelings on the matter, I can understand why you might question his figures, and conclusions, but if you want to discredit TA, AXN is the wrong choice.