Alonso was in a fight for victory with Max Verstappen during last weekend's race, and had a clear opportunity to move to the front during the critical pitstop phase as the rain came in.
However, when Alonso did go for his first stop, he elected to stick to slicks as he and the team were sceptical that the rain would last.
The move proved to be an error, as the downpour got immediately worse. Alonso had to make a second stop for inters just one lap after swapping his hard tyres for mediums, shortly after Verstappen made his own switch to the green sidewalled rubber.
The Aston pit call prompted intense interest after the race about what would have happened if Alonso had gone for inters straight away, and whether or not he and the team missed a chance to take the lead.
Asked by Autosport at the Spanish Grand Prix what Aston Martin's own data said in its post-weekend analysis, its team principal Mike Krack has revealed that it predicted Alonso would almost certainly have moved in front.
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"The computer system says that if we had gone to inters, we would have probably come in front of Max," explained Krack. "But that does not mean we would have won the race.
"So, in the full benefit of hindsight, that would have been the case. But when you make these decisions, you have to rely on the data that you have."
Alonso himself has stood by the call he and Aston Martin made, with Krack clear that what happened last weekend will not trigger the team to take more risks in the future.
Asked if he anticipated the team being more aggressive on strategy from now on, he said: "If aggressive means gambling, the answer is clearly no. We are not gamblers.
"We are a data-driven team. We look at all the information we're having. So, if that is what you mean, then the answer is clear."
While with the benefit of hindsight Aston Martin would have done something different, Alonso thinks it unfair the squad was criticised for what it did.
"What I don't like in F1 is that we see always the negatives and we always see everything very easy from the sofa," he said.
"I tell you an example: if we stopped for inters, this week we will only talk about the wrong decision of Red Bull because they stopped one lap too late with Max.
"We will never say that Aston Martin was very brave and chose the right tyre. We will only talk that Red Bull chose the wrong tyre and stopped Max one lap later.
"This is just the mentality of F1, the unlimited search for perfection which is not possible to reach sometimes."
Krack said that facing such criticisms was part and parcel of being a leading team in F1.
"That is the nature of F1, and it is something we have to live with," he said. "We are exposed.
"We want it to be reported when everything runs well, so we have to accept if reports are coming out that things could have been better. It's not really a drama."
