Hey,
I just bought the Surface Pro 7 i5 128gb version. This is my first Surface and I absolutely love it. But the problem is, I am also struggling to get more than 5 hours of battery life with just surfing on edge and using Microsoft word mostly. I downloaded the latest firmware and drivers but nothing has changed. I wanted to try the solution you posted but wanted to make sure, does the HD video have to be downloaded on the surface or can I play one from online? If the battery life doesn't improve I will most likely have to return this and go with something that gives me a bit more.