I was thinking about something a little similar - specifically in trueborn with HW grenades used with the duke. Splinter weapons out the biscuit in a venom, plus duke. They swing around the side; splinter something to hell which the duke has split off to charge, and they go prowling around causing nonsense to infantry with their 3+ splinters or - if really needed - they can take out armour with their HWGs. From a very compact unit I think you could really mess up an opponents back line or at least give them a headache dealing with it. This is for a smaller list, mind - I don't think it would work at 1.7+. Not sure if it will work at all, to be honest.