Observations of results from different setups

I don’t mean to be difficult here, but I did take time to go educate myself further on MLAT and I keep coming across mentions of GPS PPS helping with MLAT calculations. I’ve even found threads on this forum describing just such a thing:

ads-b-flight-tracking-f21/mlat-on-pi-t20106.html

“You really need microsecond-level precision to do MLAT.”

As well as a few others:

satsignal.eu/raspberry-pi/dump1090.html

web.stanford.edu/group/scpnt/gp … an_WAM.pdf

books.google.com/books?id=qJcrj … ps&f=false

I understand that GPS locations can be spoofed or set manually, but it would appear that PPS can be valuable to MLAT calculations. Am I missing something here about the method employed for MLAT or something?