PokerJunky said:
What I need to understand is what makes the HO2 system obsolete?
The problem with HO2 lies in the side-count accuracy - the means and and methods by which the Ace-density is factored into the betting accuracy is typically insufficient - resulting in harder work to -at best- accomplish the same net gain of a good Ace-reckoned level2 system, like ZEN.
Thus, to get full published performance from HO2 it is not adequate to simply estimate relative Ace-density per 1/4D as advised by HO2's developer Humble, Blackwood, and others.
The above insufficency is described by Snyder here and is a wake-up call for anyone who mistakenly beleives that HO2 is superior in real-world application -
http://blackjackforumonline.com/content/sdcnt.htm
After you have read and understood the above essay, then you may read Snyder's first analysis of ZEN published in '81 -
http://blackjackforumonline.com/content/hundred.htm
Some may say that '81 was long before the SCORE comparisons were made, BUT the SCORE comparisons between ZEN and HO2 ASSUME full complete side-count conversion accuracy, which as I say is a non sequitur, whereas a SCORE comparison between say HiLo and ZEN shows a valid increase in gain.
Notwithstanding the above, given that you have been playing HO1, you might be best served by merely switching to HiLo, adding more indices, avoiding minus counts, and learning rudimentry shuffle/cut-off tracking so that you can recognize easy to exploit shuffles. zg