Newey said that Red Bull's domination during the second half of the season was also down to them improving their car - extra performance they were able to exploit because of the greater durability of the tyres.
"We made some decent steps," said Newey, Red Bull's chief technical officer. "We actually introduced quite a few parts to the car, some of them in Hungary.
Best action from Vettel's amazing year
"And really Hungary was one that got away for us in as much as I feel that was a weekend we didn't manage to deliver the full potential of the car, partly through set-up, although partly what ruined our race, of course, was Seb getting stuck behind Jenson.
"So that was a disappointment that perhaps masked where we'd got to in Hungary. In other words, we'd got further than it showed.
"But there was no single magic component or magic bullet to our upturn in performance.
"It was a number of components and we'd had a couple of races we probably should have done better at.
"Silverstone should have been an easy win [after Hamilton's retirement] but we had an input shaft failure [on the gearbox].
"A bit of it was nature of circuit as well.
"The circuits we had as we got into the second half of the season suited the car - in as much as we'd been competitive on the medium-downforce circuits such as Bahrain and Montreal earlier in the season, but we hadn't fully got on top of the high-downforce front-limited circuits, such as China and Barcelona in particular.
"So Spa and Monza suited us as being medium and low-downforce circuits. And then by the time we got to Singapore, we managed to get on top of the high-downforce areas we'd struggled with a bit earlier in the season."
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Newey said Ferrari's early season form - and the run of eight pole positions in nine races achieved by Mercedes, from the third Grand Prix in China to the 11th in Belgium - encouraged Red Bull to push hard with their car.
That push went even as far as to reducing the effort Red Bull were putting into the 2014 car, which will need to take into account the new chassis and engine rules set to take effect.
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