It was most certainly not "generally assumed that Alesi was faster, or would be faster", but not necessarily the opposite, either. I think most people were genuinely interested in how the prodigy would stack up against an established ace. I had never been a particular fan of Prost, stemming from my support for René Arnoux back in the early eighties, but over the years I had come to accept his superiority over the field, which in my humble opinion at least also included Senna, and even learned to admire him for that. For me, personally, the outcome of that particular "duel" was not a surprise, but very much as I expected it to be. The surprise for me, at the time, was the lack of performance from Ferrari. You say they weren't so bad, with Prost coming second three times (exclamation mark!), but you have to realize that Prost had been in with a chance of winning the title in 1990, and finishing second was simply not good enough, neither for him nor for the team. Going a full year without even a single win was just a desaster, and back then I had a hard time accepting or even only understanding it - what had gone so terribly wrong? I'm sure I wasn't alone in posing that question!
Looking back, I think we were all victims of a slightly deranged perception. In 1989, Ferrari had been generally no match for McLaren; apart from a few flash-in-the-pan moments and the occasional slip-up by McLaren, Ferrari had neither the speed nor the reliability to mount a serious challenge. So, what changed in 1990? In terms of cars, not much: both McLaren and Ferrari went into the new season with updated versions of their '89 cars. But the driver pairings changed, with Prost and Berger swopping places. If you now look a the results, you can see how Berger and Senna improved over their respective '89 results, while Prost and Mansell suffered - especially the relative performances of Berger and Mansell are interesting, since they really show that Ferrari was still no match for McLaren, and if anything they were a bit worse off than in 89, performance-wise.
What skewed the picture was a healthy dose of luck, and the Prost factor, namely his "legendary ability to conserve tyres in the early stages of the race, combined with a delicacy of touch which often allowed him to run fractionally less wing than Mansell", as AUTOCOURSE put it. And the following year's AUTOCOURSE opened its Ferrari manoeuvre critique with: "The famous team from Maranello surged into 1991 on the crest of a wave of misplaced confidence...", which really says it all. At Ferrari (and not only there), they genuinely believed they had closed the gap, while in reality they were already slipping even further behind. And while McLaren went into the new year full steam ahead (new engine, new aerodynamic concept), Ferrari merely introduced some cosmetic changes. All the while Williams and Renault were making great strides, and with Mansell replacing the tenth most famous Belgian, they now also had a driver capable of winning a championship, and Ferrari was no longer even in the running for Grand Prix wins. Which became very obvious very early in 1991, and so in no time at all the famous Maranello Panic set in, and the rest is history. Of course, compared with the following two or three years, 1991 was still Gold Standard for Ferrari, but people didn't know that then; they only knew how close Prost had come in 1990.
Edited by Michael Ferner, 10 May 2019 - 17:59.
