You cannot argue that amaral misunderstood the value of the alerts and the dna. Amaral is on record using the alerts to prove Maddie died in 5a... that is total rubbish
Chief Inspector Tavares de Almeida said he believed the British child had died in her family's apartment in the Algarve resort of Praia da Luz on the day she went missing. He told the court the main evidence for this was the findings of British police sniffer dogs sent to Portugal to examine the flat. The McCanns' lawyer, Isabel Duarte, challenged this claim, arguing that the results from sniffer dogs did not constitute proof and were not allowed as evidence in the case.
I wouldn't say total rubbish... maybe there was a translation issue... or maybe he acted too quickly without a full understanding - but the fact remains that the report on swab 3a states:
An incomplete DNA result was obtained from cellular material on the swab 3a. The swab contained very little information and showed low level indications of DNA from more than one person.
However, all of the confirmed DNA components within this result match the corresponding components in the DNA profile of Madeline McCann. LCN DNA profiling is highly sensitive it is not possible to attribute this DNA profile to a particular body fluid".... and later regarding one of the swabs from the car containing 15 (out of 19) DNA markers that MM has: .... "Is there DNA from Madeline on the swab? - It would be very simple to say "yes" simply because of the number of components within the result that are also in her reference sample?"
So although he's over egging the pudding - any officer would at this stage be highly suspicious. Interestingly here's how a book by the author R. Cooley writes about the discussion between the two forces:
"The significance of the DNA is hotly debated to this day. There are very few true experts, so most of the opinions are swarf. However, a UK expert said something interesting in the presence of the Portuguese when the findings were being downplayed… "At our insistence, Stuart contacts the FSS [ the English forensic laboratory ] and asks them if they think the Portuguese are idiots. We hear him saying: “With a lot less than that, we would have already arrested someone in England.”"