This may be the "new normal" in the Tim Cook era. His background is in supply chain management.
Something to point out is that Steve Jobs, for all his greatness, liked to tinker with products until the very end. While it made for great products, he took it to an extreme. That Apple was able to get ANY supply so quickly after some of Jobs' last-minute changes (supposedly he changed the original iPhone less than a month before the launch) is a testament to Tim Cook.
Now that he's in charge, he's less likely to make last-minute changes to the designs that Jony Ivy and the engineering team put out. While it could mean that Apple is a bit more tolerant of "compromises" (such as going with the older LTE chip, the 45nm Samsung process for the A5X, and the resultant larger battery), it means that Apple has more time to ramp up in anticipation of a product launch.
That may be why Jobs had the foresight to place Ive's design team in a unique position within the org chart (I believe he has a dotted line to the Board and doesn't report directly to Tim Cook). By doing so, that keeps design "compromises" somewhat in check.