Well, the way the D lined up in the 4-2-5, I was able to pick out a couple of different fronts and LB alignments that would transition quite well to a true 3-4. For example, most of the game, K. Davis lined up in a 1 technique (just like a nose tackle but shaded to the field side most of the time) and the guys on either side of him (who would be the DEs in the 3-4 front) were lined up over the tackles but shaded in the same direction as the NT. The 4th D-lineman was lined up basically in a 4 point stance a little inside where he would be if he was an OLB in the 3-4. The "extra" DB was lined up opposite in essentially the other OLB position.
In other words, they were running the principles of a 3-4 but 'disguised' as a 4-2-5. Considering the 4-2-5 can essentially be a nickel package for a base 3-4, I'm not suprised.
My real gripe is how little pass rush we saw until late in the game, and only against the 3s and 4s on the o-line. Though whether this is an indication of a lack of pass rushing capability of our D-line or a statement of how much improved our O-line is I can't tell. We'll know come fall.