This is the nub, I think. For a knock-on into the in-goal, even accepting an argument that advantage law trumped Law 12.1(c), you end up at 22.7 in which 22.7(b) tells you the same as 12.1(c). But for a knock-on in-goal, 12.1(d) applies and has no similar support in 22.7 for being a special case.
I realise others have said similar earlier in the thread, I just found it instructive to go through it step-by-step.
[LAWS]12.1(d) Knock-on or throw forward inside the in-goal. If a player of either team knocks-on or
throws-forward inside the in-goal, a 5-metre scrum is awarded in line with the place of
infringement not closer than 5 metres from the touchline.
22.13 ATTACKING INFRINGEMENT WITH SCRUM SANCTION
If an attacking player commits an infringement in in-goal, for which the sanction is a scrum,
for example, a knock-on, play is restarted with a 5-metre scrum. The scrum is formed in line
with the place of the infringement and the defending team throws in the ball.
22.14 DEFENDING INFRINGEMENT WITH SCRUM SANCTION
If a defending player infringes in in-goal, for which the sanction is a scrum, for example, a
knock-on, play is restarted with a 5-metre scrum. The scrum is formed in line with the place
of the infringement and the attacking team throws in the ball.[/LAWS]
I just cannot see how anyone can read that and decide a 22DO is in order. 22DO is NOT mentioned in this Law OR ANY LAW that mentions a knock on in-goal. No amount of fancy word play can make that knock-on or throw forward disappear.
If you award a 22DO after the ball has been knocked in-goal then you are
wrong!
We are just going to have to differ.
Personally, I have never seen any referee at any level from grass roots to elite, award a 22DO when there is been a knock on in goal
Treadmore you are spot on. Starting with the Law that's the only conclusion you can possibly reach. Others are starting with their pre-conceived outcome, and trying to work the Law to arrive at it.
Those "others" include every other referee on the planet.