Following on from the question Reset an Arduino UNO by an command (software) and the excellent answer provided by mpflaga, the comment addressing option (1) suggests that there are design considerations for connecting an output pin to the RESET pin.
Option 1. or a variant can be a clean enough way to do this as long as power on transient conditions are designed for. - Russell McMahon
or more ominuously
From everything I've read, the first option is not recommended. - sachleen
Could someone tell me exactly what those considerations are? Is it that it is not as simple as connecting the two with a jumper cable - is additional circuitry (i.e. an RC timer) required, or is there a software solution?
I find the latter option unlikely as the device is rebooting, so unless the software fix is to ignore hardware interrupts (since a RESET is simply that, and the state of the output pins is unlikely to be known, or stable at reboot) for a few mS after reboot, I presume that a hardware fix is required.