Concentration Spells are truly cr°p for me just because of this.
Why use a Spell which can be cut short and most probably will, if you can use "Necrotic hands"?
Necrotic hands, totally a Necromancy feeling Spell - in the hands of our holy person - has a higher hitchance even most of the time.
And its dmg-value exceeds the healing-value of same level spells EASILY.
Clerics are armored magical offense-fondlers. :|
But "Concentration" can be good if you manage to sneak into the shadows quickly and hide your concentrating person.