Hmm okay. So I guess that that encirclement wasn't as important as I had thought.
In the Battle of Smolensk, the Germans pierced the (broad) frontline in five locations and drove about 200km into the rear within days.
In such cases, you're bound to get a lot of pockets - as the Germans did at Smolensk, Roslavl, Mogilev, Nevel, Vitebsk and probably at numerous other smaller places.
But you're also bound to pick up a number of POW's simply because your roaming around deep in the enemy rear.
So the Germans might have gotten some additional POW 's in the battle of Smolensk if they had played their cards better.
Or they might have gotten a few less POW's if the Soviets had played their cards better.
But regardless, the Germans would have picked up a lot of POW in the battle because of the breath and depth of the advance in such a short timespan.