shame it doesnt break cc hehe
i usually use it as a filler when i'm completely safe. if you shield wall and use artifact ability, you can literally spam it with no consequences. you can do the same if you use bestow faith on yourself while you spam LOTM on your partners.
i just don't think its that useful though as you should aim for the holy light spam due to light's grace shield wall application. it is however very nice when you are afraid of an interrupt, but remember you will put yourself in danger if you use it too much. it also cannot cope with the enemy team doing "normal" damage on your partner. i notice that my partners' hp stays the same and mine goes down instead, even if at a reduced rate.
i also had an occasion where i had beacon on myself, the light's saves procced (the thing when your beacon falls below 50% hp), infusion of light procced, and i had divine favor up. that was a huge heal and i was at like 65% hp so i reduced my hp on purpose by topping my team mates with LOTM and still topped myself with the holy light from 45% or something. [bear in mind this happens once every 50 games].
going back to LOTM's general efficiency, its not something you should put into your "normal" rotation. seems like holy paladin healing is all about spamming holy light with holy avenger when you can freecast and rotating wings / sacrifices correctly. boring as fuck to be fair because i feel totally weak outside of those CDs. it's not as fun as it used to be...