the intention of the restriction on Lay on Hands for rated is because:
it frees a slot (switch heal for ret)
pushes holy close to invincibility
ret shines in non-rated, wpvp (1o1), due to LoH with the advantage of his mid-range synergy based mobility (main hitter, ES, HoW, J, Exo):
there is no range class competetive vs ret (non-rated), fire mage*... lol! and the potential of irritation vs melee is skill depended, but as rare as legion artifacts right now on live.
*btw <3 glyphed bubble vs dots
ret shines due to LoH cuz (with it its a) major def cd (glyphed) every minute, 1/3hp FoL critheal every 12 secs, TV 6secs -10%damage (gylphed) divine shield, HoF, Cleanse etc.
in synergy with opponent being stunned 20% of combat (FoJ talented), snared (use SoJ/SoT as Fillers, 8sec/15sec) its close to supremacy.
ret is rated just minor due to the restriction of the most integral def-cd.
even before 5.3 (sword of light buff) ret was psycho in wpvp=non-rated (cuz focus burst thx 2 instant hp-refresh...)