Coffee is coffee ,doesnt matter if its decaff or not. To be honest I dont know what all the fuss is about. People have been putting cream [fat] in coffee for ages. Its just a fad in my opinion.
Maybe some people have a problem getting enough fats in their diet ? in which case this could be an easy way of "getting your medicine down".
Certainly this was true for me.
I just eat 1 time per day. The LCHF diet was brilliant for me at controlling my blood-sugar levels, so it fulfilled its main objective. But during my first year of LCHF I found it difficult to stop the weight loss.
I did not want to add another meal to my routine, as this would be inconvenient for me and also would add too much Protein to my diet. I wanted a way just to add more Fat, without adding any Protein or Carbs.
I discovered that adding Coconut Oil to my 2 or 3 daily coffees was the perfect solution. Added the needed kCals to my daily intake without disturbing my blood-sugar levels at all.
Later I learned about Bulletproof coffee, and I switched to this because I really like the taste of it.
I make my own Bulletproof coffee (like most people, I expect?) using regular coffee, regular Coconut Oil and good quality butter.