comparatives

Could you look at the sentence: It is as hard to turn her away as it is to a lost dog.

I believe that the second "as" is both followed and the first "as" preceeded by a sentence respectivedly. Usually the second as is not followed by a complete sentence because the second sentence is simplified. The parts that are the same as those in the first sentence are removed to avoid repetition. In the above sentence the first "as" is preceded by the subject and verb of the sentence and the second "as" should be preceded by the subject and the verb,too. But The above is not made so, which has made me confused. If the sentence is changed to

It is as hard to turn her away as to a lost dog. Would it be correct?

I would appreciate if you could explain to me how to creat comparatives in a sentence when the sentence is long and the what is between "as..........as" is much. I have tried to analyse many comparative sentence in this way, so far it has worked well. This sentence, however, doesn't work this way.

I have another question. When is the sentence after the second "as" or "than" inversed? He runs much faster than do I? or, He runs much faster than I (do).? Thank you very much.