I didn't get AOW until 2001, about 40 years after my first dive on SCUBA. I only got it because I needed a PADI card so the DMs would stop asking what my Los Angeles County certification from 1969 meant (where do they think the founders of PADI got their training?).
I came up in about the same way as Dr. Bill. Here is my 1st cert card - in 1979 there was SCUBA Diver, Dive Master, Assistant Instructor, and Instructor>
This card was good enough to take me up through 1995, 2 years after my first Mix dives and many, many air wreck dives in the 100-200 range from Maine down through North Carolina and the Islands. But to get from the pool in 1979 to helium in 1993 was a school of hard knocks and advanced courses held on the back of the boats with the guys who were doing the Big dives, it was training by mentor and trial and error, and the errors were costly in time, money, and spirit. It was a very hard school and not many made it all the way through and just dropped out.
In 1995, I got this one after taking an instructor into the Engine Room of the USS Tarpon and getting him a gauge, all he had to do was hold the bag as I did the work, To tell you the truth, I shouldnt have taken him in as he didnt have the experience to do it
. When we got back on the boat, I gave him His gauge and he asked what he could do for me, I asked him if I had passed the Advanced Diver test.
I asked for the card as by the Mid-90s I was getting hassled by shops and boats for not have advanced. Which is exactly the same reason I got my mix cert 12 years after my first mix dives.
So, just saying you have any card doesnt impress me, in fact Im more leery of divers who bost of being a DM, or Instructor than a diver who says they only have a few dives. The new diver knows they dont know, the diver with the cards may think they know, but many times havent a clue as they have been quarry commandos with a few dives in other locations thrown in.
So yes, you can go to 100 without AOW, but you have to pay your dues one way or another and you need the right mental attitude to do it with.