Hey renew has its place....if you are moving and penance, holy fire, mending are all on CD, the target has weakened soul debuff and ur still running...it's an option
on Thok too, at high stacks where it becomes nearly impossible to get off any casts, devo has been used and there's a bunch of weakened soul debuffs out i'll start tossing some renews, while waiting for better options like holy fire, mending or bribing the pally for a Hand of Protection (maybe i need some more haste for that fight and squeeze in more smites or bindings)
But yes in general renew is pretty bad for disc and used only as a last resort