undead spawn control house rule.

[Darth Stabber]

Is this a reasonable house rule:
A cleric or other class with rebuke undead, may take 20 on rebuke checks to control the spawn of undead they already control. Example: a dread necromancer just finished a battle, and one of it's wights killed some unfortunate mook. To prevent the risks inherant to wight chaining she spends a rebuke it to bring it under her direct control with a short minute long ritual.

I have this rule both as a short hand, and as a little bit of an incentive not to chain. Is this fair? The DN that prompted me to post this question can easily control anything her wights convert, but I think she is going to start vampire hunting, and given their turn resistance it would be nice to have a shortened method of dealing with that.

[bloodtide]

Why take 20? Why not just do a normal control roll?

[Darth Stabber]

Several reasons:
1) shouldn't there be some type of benefit for the undead in question being "willing" to be controlled, ie told to by it's controller who is controlled by the rebuker.
2) eliminating "uneccessary" rolls, and avoiding spending superfluous rebuke attempts.
3) provide a slight encouragement to directly control minions, as opposed to chaining.
4) if 3 is effective I don't have to be a ******* GM and smack down the patron of a wight chain just to show the player why not to chain. In the interest of party balance of course (I would never take some sort of sick joy out of brutalizing the party with a drastically increased encounter difficulty and no comensurate increase in xp gained mwah ha ha ha ha).