Someone has had easily more than 100 tabs throughout her life. She hasn't ever noticed a weird batch, or much of a difference even in potency. Someone is from the east coast of us. Someone doesn't think they have ever done DOI thinking it was acid. Someone hasn't ever had bitter paper.
The 9v battery is a brilliant description. I've heard it before. When taking 2cx, someone doesn't feel that tingle on the tongue. But, someone hasn't tried DOx. The tingle only lasts on the tongue about as long as the paper, 30-60 minutes. But, it's how someone normally determines if it is good paper. Bite off a corner and within 5-10 minutes of chewing on that corner of paper you should feel a tingle. There normally isn't much of a taste, if any. Well, when you stick your tongue to a 9v battery there isn't much taste either. Kinda metallic, kinda acidic, but definitely not bitter.
Someone would like to try one of the DOx just to compare. Maybe they won't be able to tell a difference. Someone can easily feel a difference between the 2cx and what they "thought" was acid.