That's why you'll like to be with people like Gaz/Uther/ETC who allows an easy setup for Furnace Blast. ETC can stun the enemies while Uth allows you not to get stunned/mosh pit to continue. But yeah, without ETC or Uther, Furnace Blast is kinda meh. I think the best teammates for the Butcher would be Jaina/ETC/Uther/Kael + himself. Both Kael and Jaina can use Lamb for the Slaughter to their advantage, and ETC and Uther allows for easy Furnace Blast setup. A team made of this five...

I've just come across your guide. I do agree with everything, except for lv10 and 20. Lamb for the Slaughter will always target until lv20 the nearest hero. Plus, it won't root him, but (considerably) reduce his mobility. This is awesome against Illidan or divers, I guess, but... Sometimes, it will just be useless, considering how some teamfights can be chaotic. Furnace Blast, especially with ETC or Uther (Mosh Pit's duration is 4 sec and Divine Shield lasts for 3), is too good to pass imo....

I don't agree with some talent choices there. At lv7, I think Battle Momentum would be better. While "The Crusade Marches on" only takes off 4.5 seconds on Iron Skin (you're going go use your ult before Iron Skin and I don't think using it takes off 1.5 second) Battle Momentum takes 0.5 seconds off from all basics abilities for every attack Johanna does. Her basic abilities don't have that of a high CD (8 to 12), and they are all bringing something interesting in a teamfight...