I am totally underwhelmed by the lack of robustness of the avrdude upload protocol.
It has nothing to do with avrdude, which supports MANY protocols (which is why its code is so hard to understand). This is the STK500v1 protocol developed by Atmel. (for the STK500 eval/prototype/programmer board, which WAS one of their really early products.)
It does suck; you'd think that such a simple protocol would at least be efficient and unambiguous to implement, but that's not the case either. And on top of that, it's a "programmer" communications protocol rather than a bootstrap protocol, which means it's full of command inappropriate to interacting with a bootloader.
The communications robustness was fixed (or addressed, anyway) in version2 of the protocol (stk500v2.) Stk500v2 is used on the MEGA and MEGA2560 boards; the smallest v2 implementation I know of is 4k bytes. Which is a bit much for the 328 
I doubt whether it's possible to do a 512byte bootloader with an error-checking protocol. (although WRT wireless, some relatively small changes might help a lot.)
For all the failings of the protocol, the arduino bootload process seldom has communications errors. After all, it has a separate high-speed error-checked link to within a couple of cm of the microcontroller pins.