It is completely idiotic. Each of of these programs is hard to recover from as it is. And you want to combine both? There is a difference between being able to “do something” and growing from it.
You don’t seem to really know what GVT is.
The REAL GVT has 4 exercises and 26 sets per workout.
For example DAY 1 is Chest/Back
A1. Bench press 10 x 10
A2. Chin-ups 10 x 10
This is done in alternating fashion, a set of A1, rest 60 sec, a set of A2, etc.
B1. Incline DB press 3 x 10-12
B2. Bent over row 3 x 10-12
Sure if you do only one exercise with 10 x 10 you can do a second exercise 5 x 5… but you asked about combining GVT and GVT is not 10 x 10, its an actual program. And in that case NO you can’t add 5 x 5 to it.
If you are going to ask a question about combining two programs (which is never a good idea BTW) at least know what the programs really are.