So you and I are on the same page with this stuff.Honestly, I think people use the term interchangeably.
Mostly, in my experience, "Body" as in "Full-Body" means flavor and "Strength" is nicotine content.
"Pepper" is I guess more in the "Body" area but, to me, it's a separate thing all together. Just like you can have spicy food with no flavor, I think you can have a pepper bomb with not a lot of flavor. For example, the Tat Cojonu I had last night had a lot of pepper, but the P1964s I've had have more flavor.
My understanding has always been: "body" = depth and richness of flavour; "strength" = nicotine content.
I loooooove flavour. I love cigars that run the gamut from mild to medium to full body.
But I can't take much nicotine. I'm not a smoker, never have been. If I smoke something like an LFD chisel, I will probably puke!