While I find such installs to be -> electrically correct <- you encounter installers that either don't know that there are pairs in the wires or that the pairs are not 1,2 3,4 5,6 and 7,8. I will not reveal the correct wire pairs here because I want to hear it from the installer. That gaffe happens so often it's not fun to hear/see again and again.
What makes it harder on everyone is when folk want to know why it works or not when the wire pairs are not correct or with specific hardware. That would take a deep inspection of said gear, sketching out the wire pairs and well, who is going to do that?
I wired my house with cat6, terminated into keystone jacks & plugs, etc. I could only get one of the two downstairs outlets to connect to the internet but was only testing one outlet at a time (ie. patch cable to computer). I re-punched the other jack several times, tested the wires, etc. but could not get an internet connection on the 2nd jack (all cabling is connected via switch) Finally, I plugged in both jacks to computers and suddenly both jacks were working fine. Is there any explanation for this? I'm glad they're working, but cannot think of a reason why connecting both at the same time would suddenly make the "non-functional" jack work. THanks.