The swelled edges on the lapels of some sack jackets are not lapped seams.  They are not lapped, nor are they seams.  A lapped seam is a very specific way of seam finishing.  Many jackets with hooked vents have the back seam lapped, current Press offerings do not.  Some 1950s and 60s sacks have the shoulder seams lapped, and I have encountered custom suits from the era with every body seam lapped, including the side and sleeve seams.

The swelled edge along the lapel is not a seam, it is a form of topstitching.  Just sayin'.   I am learning to tailor slow but surely and the more I learn about construction the more I realize how many misconceptions I had about this stuff.