Hmm yeah thats a good rule. And they could make it cost 5 points for the whole unit. And call the rule something like...... Musician?
Nah I guess they could also naturally win by 1. I have no problem with it, if something has gone wrong and I find my saurus beaten and outnumbered by skeletons, or even worse (and even far less likely) zombies, well it is the unit's fate.
Is it even posible for 20 zombies to beat 20 saurus? 4-5 s2 attacks, wounding on 6's and a 4+ AS, its unlikely they will even do a single wound, even if they somehow manage 2 wounds we still have 17 attacks back that are wounding on 2's (spears).