Um, you may not want to celebrate too quickly, champ...
Henry Melton switched from his end position in 2010 to the interior in 2011, and to a degree, he prospered, picking up seven sacks and even had a few calling for him to go to the Pro Bowl. When the switch was made to the interior, it was done so presumably because of his quickness off the ball and speed rush up the interior.
Unfortunately, when the folks over at Pro Football Focus ran their tackling efficiency numbers over the last three years, Melton ranked as the worst in tackling efficiency among defensive tackles and interior rushers, worse than the likes of fellow-one-time Bear Amobi Okoye (5th) and another former Bear, Tommie Harris (11th). And for a quick primer on tackling efficiency, since they've done one of these looks for linebackers and defensive backs...
As a reminder the Tackling Efficiency metric is as simple as things get - It's a ratio of missed tackles to attempts. We take Solo tackles + Assists + Misses / Missed Tackles = TE.
First off, for interior pass rushers that rotate in yet are a huge part of the team's gameplan, they set the qualifying number at 900 snaps played over three seasons, meaning Melton qualifies at 992 snaps. Over the last three seasons, he has picked up 22 solo tackles, 4 assisted, and missed six, giving him a tackling efficiency of 5.3 - meaning that he missed one tackle every 5.3 tackles he attempted. Okoye was 5th with 8.4, and Harris 11th with 9.2.
Now that we've looked at the total for the three years, let's look at Melton in 2011 in his first year playing the three-tech. By the formula they provide, we can take his 14 solo tackles, 3 assists, and five missed tackles to get 4.4 - which means he misses one tackle in every 4.4 tackles attempted. Which, by my count, isn't good.
But, the prognosis does look a bit better when it's taken with the rest of his ratings - the sacks are there and can continue to improve, and his overall rating left him in the positives, on the defensive line unit only below Julius Peppers both overall and in pass rush. And Peppers himself had a tackling efficiency last season of 8.67 and over the same three-year period, 9.1, which were he an interior player he'd rank 12th (as is, 13th amongst edge rushers).
Take a quick look through the articles - what are your thoughts on tackling efficiency? There doesn't seem to be much correlation between tackling efficiency and being a solid player.