Architects goal is to reduce irreversibility in the system.

The statement "He saw agile methods, in manufacturing and software development, as a shift that seeks to contain complexity by reducing irreversibility — as opposed to tackling other complexity drivers." by Enrico Zaninotto http://martinfowler.com/ieeeSoftware/whoNeedsArchitect.pdf" made Fowler conclude "I think that one of an architect’s most important tasks is to remove architecture by finding ways to eliminate irreversibility in software designs"

A perfectly valid conclusion.

But going back to Enrico Zaninotto's statement the part where it says "reducing irreversibility" is completely true.  But I find it difficult to to accept "contain complexity" part of the sentence. Does trying to "reduce irreversibility" actually reduce complexity of the system? My answer would be an emphatic NO. It actually would increase the complexity of the system.