tools directives in platform.txt seem to be ignored

Has anyone been able to make changes to the tools.* options in platform.txt in a custom core do anything?

I'm trying to supply a custom avrdude.conf with my core.

So I put it in the outer folder, the one in the hardware folder, with the avr folder inside it, and in platform.txt, I change:

tools.avrdude.config.path={runtime.ide.path}/hardware/tools/avr/etc/avrdude.conf

to

tools.avrdude.config.path={runtime.hardware.path}/avrdude.conf

But it doesn't seem to look at it!

Uploading an empty sketch yields:

Sketch uses 382 bytes (9%) of program storage space. Maximum is 4,096 bytes.
Global variables use 9 bytes (3%) of dynamic memory, leaving 247 bytes for local variables. Maximum is 256 bytes.
C:\arduino-1.6.5-r2\hardware\tools\avr/bin/avrdude -CC:\arduino-1.6.5-r2\hardware\tools\avr/etc/avrdude.conf -v -pattiny441 -cusbasp -Pusb -Uflash:w:C:\Users\a2\AppData\Local\Temp\build2756813214724141955.tmp/sketch_jul03a.cpp.hex:i

In fact, I can delete the whole tools section with no change in behavior! There's no way that should work... I've done a sanity check and confirmed that I'm editing the right file, and some changes are getting through. Just none of the tools.* stuff.

Anyone have any idea what might be going on here?

Being able to specify a custom avrdude.conf file is critical for custom cores - the default avrdude.conf is missing lots of chips, and I'd like to support these parts in my core without people having to modify their avrdude.conf (which is tricky due to windows UAC protections on stuff under program files.

You could create an issue / pull request...

https://github.com/arduino/arduino-flash-tools https://github.com/arduino/avrdude https://github.com/arduino/toolchain-avr

...to include an improved avrdude.conf file...

http://www.avrfreaks.net/forum/avrdude-and-attiny167

...then wash your hands of the mess.