Have a read of this article:
http://www.bullshido.org/Te_Mau_Taiaha"According to an ancient Maori proverb, Te Mau Taiaha should be taught “from the feet up”. Formal taiaha footwork patterns are based on a complex, dance-like step called karo (evasion), with many variations named for the characteristic movements of different animals. For example, the tuatara (lizard) pattern features slow, crouching, sinuous steps, in contrast with the light, active footwork of the tui (bird). "
Quote:Being pragmatic warriors, they would have simply left off what no longer worked and moved on to what did.
You have obviously never read "To Face the Daring Maori'. Whilst the Maori did utilise European Technology, they maintained and used (ferociously and with deadly consequences) their traditional fighting arts, strategies and tactics.
The Maori of New Zealand are credited with being the creators of trench warfare. Google 'Maori Pa'.