1. 0 evidence that he gets clapped worse than smoker ever would especially when smoker lost to someone weaker than boa and shiryu (vergo).
2. He can't do anything to kuzan. Now maybe his awakening (smoker) allows him to be the perfect smoke bomb and that way he could escape or help the others escape. So there is some usefulness there. But a full flegde fight? He needs to bring tsru and sengoku with him
I meant evidence or foreshadowing to help Law.
I gave you plenty for Smoker coming to save the marines with Luffy.
Coby never battled Boa or Shiryu so don't try make it out like Coby battled stronger people than Smoker in fights using that logic I could say Pre TS Smoker battled Boa at Marineford.
Law is stronger than Shiryu and Smoker battled him.
Let's be real there's nothing stopping Oda from giving Smoker a power creep. He did it with Luffy against Kaido. Sanji with Queen. If the story calls for it Oda will make any character as strong as he needs them to be.
You can't deny it doesn't make sense for Smoker to come to Beehive considering the connections with Kuzan and Tashigi being captured right.