There appears to be a confusion here, Tez, that "Unified rules" translates to "UFC rules" and that simply isn't the case. The California State Athletic Commission voted in the regulations that eventually became the unified rules of MMA. State Athletic Commissions regulate combat sports in America and in order to put on a legal show in the US you must abide by whatever state's rules you plan to hold the show in.
What kind of promotion lists a set of rules and doesn't follow them? They have a name for that, it's called hypocrisy.*
Every state that allows MMA in the US follows the unified rules, and some tweaks to procedure concerning weigh ins and attire vary from state to state. Your bias against the UFC is showing more and more as discussions where MMA is brought up occur. Every time the UFC is mentioned you appear to take it as an attack or a personal challenge to reply with as much tongue-in-cheek content as possible. MMA as a whole is a business, if it wasn't there wouldn't be "professional" MMA fighters. It wouldn't be a career choice if it wasn't a business. But I digress.*
You said you have been around since MMA began. I'm sure you mean MMA as it is today as in post UFC 1. While you may know the UK MMA scene it is very clear you have little interest/knowledge of MMA outside of that. Being unfamiliar with the term "unified rules of mma" which were introduced and adopted across the globe circa the year 2000 is yet another piece to that particular puzzle.*
What you may not know is that MMA has roots that stretch back directly as far as one hundred years ago in Brazil and Japan. It was commonly called "Vale Tudo" in Brazil and featured renowned fighters like Carlson and Helio Gracie, Waldemar Santana, Rei Zulu, Ivan Gomez, Mashaiko Kimura(the maneuver's namesake), among others. These bouts took place in all manners from ads put out in newspapers with open challenges for cash prizes, to in a ring in front of a crowd as exhibitions. Varied styles from catch wrestling to Judo to Jiu Jitsu and Boxing, Muay Thai, and Kickboxing specialists looked to match their art with one another.*
Yeah yeah, have a bash then move on. Assume the Brit is ignorant and knows nothing. Gee imagine my amazement when finding out that Vale Tudo was the forerunner of MMA, I must tell my mates who actually fought in Vale Tudo fights, they couldn't have known what they were doing, nor could I really if I was there too. I'm surprised you forgot to mention Pankration, still done in Greece,( in 1895 they refused to put it into the Olympics) has been for more years than the UFC has been going. Thank you for your lecture, totally unnecessary of course, but it'll make you feel better. Shame you haven't read my posts but there you go.
Btw as for knee strikes being legal in the UFC, if they weren't illegal why did they need to say they were now legal?