Arduino Mega2560 as ISP to program another Arduino Mega2560

It is equally a bug that the "bootrst" fuse is left programmed (0) on a m328 when you do "upload using programmer." It only works if the sketch is short enough not to overlap where the bootloader WOULD be...

This was apparently reported a long time ago, but never understood well enough to fix. I've added a comment to the bug.