We are Getting in the Box more than everyone else

The latest stats we have say that the industry average of open rates is 26% and Pure's is 33%.
How much of this is down to the emails actually getting into the inbox rather than redirected to the spam.junk/bulk folders?
Could this be down to our whitelisting and Spam checking?

This is an interesting point,

Could it be a good handler on whitelisting?
Could it be a good selling point?