Yes, I'll be relaxing this weekend and yes relaxers have to be neutralized. I'm just not convinced there is a special neutralizing ingredient, the pH is most important.
Judging by some ingredient lists, I compared a moisturizing and neutralizing shampoo from the same line and they literally had identical ingredients. My stylist I went to for 6 years never used one(at first I didn't know because I wasn't into haircare)and my hair was very healthy.
You're right, I'll order some. The Affirm Normalizing Shampoo has a pH of 6 and the 5 in 1 reconstructor you use before is 4.5, I'm not sure about other brands.