Brian Greenstone, if you don't know, has been writing games for years, starting on the Apple //gs, if I remember correctly, then moving to the Mac, then later the iPhone. He knows probably better than any living person - at very least any living person outside of 1 Infinite Loop, Cupertino, CA - how to get the best 3D performance out of Apple hardware, so if he suggests something, it's a good idea to listen.
To discover whether Vertex Array Ranges were supported, I used the following code:
NSString *extensionString = ;Which simply dumps a list of the OpenGL extensions supported by the device to the console. Here is the list I get when running on my first generation iPhone (Note: running against the simulator will give you a slightly different list):
NSArray *extensions = ;
Unless I'm reading it wrong, it looks like vertex array ranges are not supported on the iPhone.
Let's hope Brian decides to write an iPhone Ultimate Game Programming Guide.