Elhardt:
The term"irreducibly complex" is a contradiction in terms.
Irreducible means:
"r`re`du’ci`ble
a. 1. Incapable of being reduced, or brought into a different state; incapable of restoration to its proper or normal condition; as, an irreducible hernia.
2. (Math.) Incapable of being reduced to a simpler form of expression; as, an irreducible formula.
Irreducible case
(Alg.) a particular case in the solution of a cubic equation, in which the formula commonly employed contains an imaginary quantity, and therefore fails in its application."
While complex means:
"# (n.) Assemblage of related things; collection; complication.
# (n.) Composed of two or more parts; composite; not simple; as, a complex being; a complex idea.
# (n.) Involving many parts; complicated; intricate."
Quite simply a thing that is irreducible cannot be composed of more than one part while a thing that is complex has to be composed of two or more parts.
Given the normal usage of the English language a thing cannot be both irreducible and complex.