As this started from a comment about the pronunciation of the plural of 'cervix', and I then mentioned 'index' as being a similar word. Steve's latest comment seems to totally ignore these to go off on a tangent.
Clearly he has found something in 'stack exchange' which supports his view.
I'll quote from that same source: Stack Exchange
Kenneth Wilson, The Columbia Guide to Standard American English (1993) notes that both plural forms are currently standard in English and then focuses on the idea of "foreign plurals" versus "regular English plurals":

index (n.) has two Standard plurals: indexes (pronounced IN-deks-iz) and indices (pronounced IN-di-SEEZ). See FOREIGN PLURALS [where Wilson makes the following relevant observations: "But when loan words cease to deem foreign, and if their frequency in English increases, they very often drop the foreign plural in favor of a regular English -s. Thus at any given time we can find some loan words in divided usage, with both the foreign plural (e.g., indices) and the regular English plural (e.g., indexes) in Standard use."]

Wilson seems to take the view that, all things else being equal, indexes will eventually win out over indices as index becomes less and less a foreign loan word and more and more a naturalized English word. This same expectation probably underlies Garner's view that insisting on retaining a word's original "foreign plural" form is pretentious once the word (in its singular form) has been fully subsumed into everyday English.