I am gutting my house and need to frame a few new doors and remove a few
doors.

In close examination, the way the existing doors are framed is very
different from what I have seen typically done. Here is a picture of the
door frames of two adjacent doors.

http://i173.photobucket.com/albums/w...e/P1010217.jpg

The right side is the rough frame of the door, looks typical. On the left
side I removed the piece of wood that is vertical. Normally those are just
1x6 nailed onto the 2x4 stud right? I pryed out one piece and was surprised
it is a piece of 2x6 routed on both sides to form a "T" section. So the
wider part is on the outside and the drywall stops short of it. Here is a
picture of it's cross section.

http://i173.photobucket.com/albums/w...e/P1010221.jpg

The house is 35 years old, I wonder why it was done this way, and whether
there is any advantage of doing it this way. If I have to frame new doors
should I use this method to be consistent?

Thanks,

MC