Naw just the area of the weld. A Post Weld Heat Treat for most purposes' is to relieve residual stress's created by the shrinking of the weld it is often referred to as "Stress Relief"
That is one of the reasons Gradient control is important to prevent creating more stress in different areas.
What is you back ground and what kind of work are you doing? if you don't mind my asking?
If you do or do not PWHT the coupon B/4 you bend or pull it, that information is called and "Essential Variable" and become a part of the PQR just like Volts/Amps, base material and Filler.
A PQR usually needs to be tested for properties like tensil strength and others like hardness. PQRs can can be used provide a great deal of Metallurgical information but for the most part all you need to get a WPS is the Essential Variable.
I am not a Welding Engineer by any stretch of the imagination just done a lot of PQR's, WPS's and PWHT's.. By done I mean physically carried out the work and recording the variables.
There are a great many minds here (much better than me) if you give a little more info about your self you maybe amazed at the level of expertise you can tap here.