roasted steak seared right at the end spends relatively little
time in the hot skillet, resulting in more evenly cooked meat
throughout.
Take a look at these two steaks below: the one on the left
was cooked using the traditional hot-skillet approach, while
the one on the right was cooked as part of a whole roast,
then portioned into steaks, followed by a sear. Both have the
exact same internal temperature, but there is far more
perfectly cooked rosy meat in the roasted-then-seared steak
than in the traditional steak.
Traditional searing leaves a gray ring.