> The only way we have to distinguish if we are in a register or login forward is its current_url param

No, the idea would be to trigger a ```'forward' , 'register'``` hook from the register action. The 'register' parameter would allow handlers to know that the forward is being done from that particular action.

BTW, why is the ElggUser being passed to the hook? It's not used currently.

If it's not used, wouldn't the simplest way be to just call ```forward('register')``` from the register action and then have uservalidationbyemail register it's ```uservalidationbyemail_after_registration_url``` handler to ```'forward', 'register'``` triggered inside ```forward()```?