If you are speaking of notching the casing, I would say yes as they both need to terminate somehow and that works from my perspective. My only question would be is if that aluminum rectangular tube is actually a part of the door or not as I have not seen an open extruded pc of aluminum used in that manner before..

I agree… Thank you so much!

Never seen that in my previous homes. Unfortunately I was not present during intallation.

" Never seen that in my previous homes. "

Never seen that in my 40 years in the window and door industry. Albeit commercial the last 15, I am still somewhat in the loop on residential products.