You havs just defeated your own arguments.
I didnt say he would be a failure I said he is unproven In the EPL. His scoring ability is not in quesstion it is whether he will fit into Chelsea system which as yet is unknown. As you said he didnt fit into Spains system. So who is to say without doubt he will be a hit with Chelsea.
Because Spain play totally different than Chelsea. Spain plays like Barcelona and he just don't fit into that system. Chelseas style resembles more the style of Atletico and I think he'll fit in brilliantly into that system.