Obamacare was certainly not well understood prior, on or even after passage. Regardless of what you say occurred, the actual bill passed was forced thru with, as Rep Pelosi said, "We will see what is in it when we pass the bill" (paraphrased).
1) This is factually false and a distortion of what she said. Her statement had nothing to do with what Congress would see, it was that after the controversy died down the public would be better able to evaluate what was in the bill.
2) While I can't quantify what you consider to be 'well understood' it was drafted in a transparent, public manner, the bill was repeatedly and openly scored by the CBO, and the bill was available for both the public and the Republicans to critique and provide input on. All you need to do is go back and read the news about it at any time during its drafting and you can see that the legislative language, while constantly being revised, was open for everyone to see for quite a long time.
None of this is true for the AHCA. Literally no one has seen the language of the bill outside of the people crafting it, and this is on purpose. This is the exact opposite of how the ACA was drafted, and saying 'both sides' just enables bad behavior by conservatives. This is the single most irresponsible act of major legislation the country has ever seen. They are literally trying to remake 1/5th of the US economy in secret with no public input, no expert input, and no input from the opposition party. This is insane and everyone, Republican or Democrat, should commit to voting out every single legislator who took part in this process.
Nothing is open about any of this healthcare crap. The best we can do is scrap it and open up competition across state lines and disconnect healthcare from employment.
This is a good example of what I'm talking about. There is NOTHING preventing insurance companies from competing across state lines. In fact, the ACA actively incentivized them to do so but they declined. This is because building provider networks is really hard, not because the government is standing in the way. If you repeal the ACA you will make competition across state lines LESS likely, not more.
I do agree we should disconnect health care from employment, but good luck on that one.