I toyed with the idea of a refused flank myself. But we are forgetting one thing. If we are fielding a combined arms Empire vs such an army, we will have LESS units to plonk down than he does. In a deployment phase, when he can plonk down 11 to 12 units. You are going to need to plonk down more than that before he puts down his last (and most powerful units).
I don't see that happening. Because he has so many units. He would probably end up putting down his last units after you do. (If you guys deploy based on a each one places one unit basis). Once this happens, your refused flank faces his weaker units. And your strong flank will face his toughess units.
He doesn't need tons of heroes. He is taking less than 4. His lord general was doing so badly (because it was a natural target) that he swopped it for a hero (master). The army really is based on TVI where by killing any unit, even the executioner unit doesn't mean end of the game for him. You could focus on one unit, then his cauldron will place a 5+ ward save on that unit. And he will then flank you can destroy you with all his rest. Read his battle reports. A lot of players thought his executioners were an easy target and charged them. But with cauldron and banner, its his strongest unit and it has faced off and killed very powerful units before.
About the cauldron. Only flyers would be able to get close, and normal weaker flyers might not be able to do the job because the cauldron is protected by a hero level hag. For us, it would be our pegasus captain. But note, the cauldron has terror. So, we have to pass that first before we try and charge it. Then our captain has to beat his hag on a one to one fight.
Through all his battle reports, he has rarely lost his cauldron. He has so many threats on the table the opponent doesn't have time to focus on his cauldron. He usually keeps his cauldron behind some terrain so that it still gives its power to the troops while its hard to charge it.
He has so much units he can field weaker ones in front of his stronger ones. His witch elves and spears are leading the charge with his black guard and executioners behind. So he has a missile screen. He faced a bret army with knights and all wizards plus the player had comet of cassandora, which he couldn't block! He still won that army.
I don't know about it being unfluffy. Its a really strong list, but in a fluffy way because he takes zero dispel scrolls, has like just 2 dispel dice for defense, and not a lot of shooting. and zero big monsters. How do you call such a list bent? Most people looking at it first hand would think they are facing a weak list, one which is weak for the sake of being "fluffy". But it works, in an extremely efficient way because it excels at one thing, killing!
I want to counter this type of army without having to take 4 mortars and 2 helstorms. Because we know how well that is going to fare against all other armies.