His listed height is incorrect.
IMDB lists his height at 6'2 and if you look around the net, you'll get 6'0 or 6'2. But look at this pics of Robbie and Stephen Amell. Stephen is 6'1, but is noticeably taller than Robbie.
https://fbcdn-sphotos-e-a.akamaihd.net/hphotos-ak-prn1/941180_44680591 5404681_2068930639_n.jpg
He can't be any taller than 5'10.