I didn't watch the video, but I disagree on this point. Level 1 W, when all three are placed in your lane, gives you about 250 extra health for whoever needs it and infinite sustain with the headstart of three Shrines (if you're not getting poked hard, you can replace them as fast as necessary). Or, you can give Shrines to your mid to ease them into a difficult lane or your jg to enable early ganks - I find top to be a bit too far with the earlier spawns.
Starting Q gives you decent level 1 poke, especially with Thunderlord's, but few ADCs can make big plays off a level 1 stun that the other ADC/Support won't have some way to nullify. W has more overall utility, and you can just take Q second - there probably won't be any action in your lane until then. And if you place your Shrines well, the other Support/ADC won't even know you started W.