Yes, I find the relational aspect pertinent when engaging in debate, and there are various dynamics at work - here's just two which exist.
One is debating online, where there is no body language to assess. It is purely the written word, which as we all know, emoticons or not, can be misunderstood.
Two is in person, face to face. If someone, with smiling eyes and laughing face said they thought I was delusional, well then, I would understand much more instantly that it was said with no harmful intent. It might well have been said with conviction, but the manner in which it was relayed would, to some extent, influence my emotional reaction.
However, if it was said with cold, flat eyes and a tone of voice which I found unpleasant, then my emotional response might well be quite different.
.......until such time as I had analysed and unpicked it all and discovered they (and I) might possibly all have been talking gibberish, of course 