If you are correct, then you can only protect three of them and your opponent shouldn't be wasting whole squads firepower on picking off lone models one at a time.
The enemy should be shooting at your troupes before they get into combat, not the death jesters.
If the misdirect power is used and is effective, then this means the enemy that wished to fire at the death jesters must choose another target and they're gonna shoot your troupes instead.
The shadowseer should be leaidng the troupes, besides he's pretty nasty in combat and has the veil of tears power which is totally wasted if he's sitting waaay back.
Also if you have a wraithlord next to the harlequin squad lead by the shadowseer you can use misdirect to make the enemy shoot at him instead and their basic weapons will have no effect
That's just my view on it.
Have you written any harlequin stuff for EOL yet?