Why are you adding the odds from the first round and incorporating them in the second???
If you lose the first round, the odds do not carry over. They are erased. We do not gain any advantage from our first draw loss what soever so adding them into the overall odds is wrong.
You are right that the outcome of one round doesn't affect the probable outcome of the next.
Keeping in mind that I am probably a moron at this, here is one way I've come to think of it:
Imagine that you try something three times in a row, with a 20% chance of winning on each try, and you repeat that process 100 times.
You would expect that in 20 times out of 100, you would have succeeded on the first try and would not go on to the second or third tries.
Of the 80 times you failed on the first try, you would also fail 80% of the time on the second try. Therefore, you would expect to succeed 16 times and fail 64 times in those 80 tries.
Of the 64 times that you failed on the first and second tries (combined), you would also expect to fail 80% of the time on the third try, resulting in success about 13 times (rounded) and failure about 51 times out of those 64 tries.
After doing this 100 times, you would expect to succeed 20 times on the first try; 16 times on the second try; about 13 times on the third try; and there would be about 51 times left over that you did not succeed on the first, second or third tries.
I think this logic resembles the tables showing a likelihood of success of 52.5% in the first three rounds, when you consider that the odds are not static and will change from round to round as the field is thinned.
I can't do the actual math, but that table sure looks right.