Looking at Michael Bertiaux's Voudon Gnostic Workbook makes me think about the discussions and petty fights between practitioners of Traditional Chinese Medicine and doctors of Western Medicine. The TCM professional looks at the person as a whole, the western physician looks at the acupuncture points he has to needle to get the results he wants and doesn't care about the deep underlying mechanisms of Chinese Medicine. No wonder then, that the results of the western physician are not lasting - or need to be supported by additional western practices and drugs!
One of the most quotes African proverbs that springs to mind when looking at Bertiaux is "in the land of the blind, the man with one eye is king". Vodou is not a tradition of spell-casting, conjuring and invocation/evocation. It is a way of life and a practice to achieve alignment with ones destiny by creating health, wealth (not riches) and happiness. Unfortunately Bertiaux does not portrait vodou in this way but makes is a cheap, dark and "powerful" practice to support his chaos-magical practice. But even power is understood differently in vodou then how Bertiaux presents it - the power vodou teaches us is not power over others (or over the Loa) but over our own lives.
I could ramble on more, but I doubt it will change much! Chaos magic will always be chaos magic and once exposed to it, its difficult to change your mind and understand that spirituality could actually be more then a means to an end that can be used at your leisure!