Monitoring your apps to get a baseline is a great idea. It's one that I wish I'd been a part of but haven't ever been. At my old job there were sometimes when the web app providers used to enter billing services appeared to be running slow. Or so they said. It was a small IT shop, where the two of us wore several hats. But neither of us had network skills, so we didn't know what to do. Sometimes we could tweak a page to improve performance, but other times the best we could do was hope it went away.
In my current job the IT shop is much larger. There are networking people, etc. Occasionally I'll hear something running slow, but I think it's handled most of the time it's handled by someone in Ops. I've no idea what they do, whether they monitor systems and develop baselines or if they just react to what's happening at the moment.
Kindest Regards, Rod Connect with me on LinkedIn.