Packers have been working on moving CM3 inside more [for 2 years] in 2013 and '14 seasons; part of the reason was to get Perry more snaps.
Perry is an extremely valuable player. On thing the stats dont show is how assignment sure he is in the run and holding the edge. And though often he's removed in passing downs his pass rush stats are pretty darn good.
17 games, five starts (429 snaps; 34.7 percent of total defensive snaps), 30 tackles, six missed tackles, 4.5 sacks, 13 quarterback hurries, zero interceptions, one forced fumble, one pass defensed, one penalty committed, 22 stops (tackles that resulted in offensive failure); dropped back in coverage 20 times, targeted three times, allowing two receptions for 23 yards and zero touchdowns.
Now for comparison purposes lets assume he played every snap and triple his stats:
90 tackles; 13.5 sacks; 39 hurries; 66 stops
And his extrapolated 2013 #'s: 86 tackles; 13 sacks; 61 hurries; 8 forced fumbles, 5 missed tackles [playing 38% of snaps] and worse in pass coverage showing he improve in that regard from 2013-14.
These full season numbers are not just good; but HOF good. For 1/3 of the snaps we have a back-up playing on a HOF pace.