Yep he would've massively beneficial for Finn. There's really no one of that aura and knowledge in NZ, who knows the core of batsmanship but is also able to see its application and worth in the shortest forms.I wonder sometimes if Martin Crowe might have been able to help Allen develop a more robust approach. He was apparently mentoring him when he was a teenager and might have been able to work with him the way he did with Taylor and Guptill.
These young guys are generally growing up under the tutelage of fathers coaching that think T20 is all swinging merrily from the hip.