Could've been. Or atleast, the book was written with two or more people. Certain context clues can lead us to this conclusion, like the following quote from the SWE Shift:
S.W. Erdnase said:
We have not dubbed the following process with our initials
because we wish to appear "big on the bills," but merely to give it a
name.
Yeah, definitely. I just wanted to add that as a bit of extra info. Personally, I don't buy the whole two author thing for a variety of reasons, but it's possible Erdnase had advice and some contributions from a second person.