This feature would be really useful for jumping back to where you came from, when you do multiple jumps and browse around in various files.

Just a note, C-]which pops the tag stack, is different to C-o, which is not necessarily jump-to-definition-related. The stack for C-o gets modified very often, for example when doing gg , so simply using this key would not be ideal, as I often have to press the scheme the times to come back to where I was before using the jump to definition feature.