If we apply it onto heal and shields where if a heal or shield is use consecutively on a champion it will lose effectiveness up to 70%. First heal/shield = 100% Second = 90% Third = 80% Fourth = 70%
This way it will allow supports to spread their utility around the whole team instead of being a heal/shield bot for the ADC. Raka/Janna should not be able to spam at over 100% effectiveness thanks to the thing you call 
Silly Neeko1 votesI find it funny how you say that about Janna..... but Lulu with 45% cdr can recast their shield before the first even wears off. Janna can not. Raka is, always has been, and always will be a heal bot. "Hey over here, come here for health!"
z63XnLCMwX1 votesI find it funny how you say that about Janna..... but Lulu with 45% cdr can recast their shield before the first even wears off. Janna can not. Raka is, always has been, and always will be a heal bot. "Hey over here, come here for health!"
Janna shield gives AD. But you're right, Lulu is cancer as well.
Silly Neeko1 votesAnd has a longer cooldown on shield. Lulu's shield lets them rapid fire Pix who can be shooting for 30+ damage each bolt and it has 3 of them? Mabey 2.
Janna gives like 30 AD. Mabey 40. Yes, roughly another BF sword at max rank with good ap....... but that to me is meh. They have to actually make use of it. Meaning they have to actually hit.
Zyra and Nami both punish Soraka and Janna fairly hard. Blitz does as well, and Thresh is just evil vs Tristana who is normally paired with them.