stacked command shortcuts

Has anyone checked out the stacked keypress functions in 3DCoat? It's my favourite thing about that program, plus having a key bound specifically to assign any button to a shortcut key. So you can press a key, tap on any UI button, then it asks you for a key to assign to it. Let's say you tap 'a'. You can then do the same on another UI button. if you tap 'a' again, you can decide how it assigns it. You can override the current Ui button assigned to 'a' (which is what most apps do) or you can stack the command to it treats 'a' as a linked list of commands to cycle through. If Blender 2.8 could do this, you could assign, let's say 'd' to 'Draw Pencil' and then again to 'Draw Ink' and then again to 'Eraser Stroke' and just by tapping 'd' you could cycle through your chosen selection of tools at any time, and easily and quickly reassign it too if there was a button bound for UI button shortcut assignment.