Re: Any thoughts on this?
Please use more descriptive subject lines! Many people here only answer specific kinds of questions, and there is no telling anything at all from your current subject line.
That extra line coming from the bottom of the skimmer to the pool is called an equalization line. They are fairly common on commercial pools, quite rare on residential pool. An equalization port has both pros and cons. I don't prefer them because they add additional places where you might have a leak, though the odds of that are low. They also add expense, which is probably why they are not usually installed. There is a case where that can keep the pump from running dry, there are also other cases where it won't help. Most people consider it a net positive, but it isn't a huge difference either way.
Connecting the pool rebar to the deck has far more dramatic pros and cons. In nearly all places it is considered very bad practice. However, there are a few areas where soil conditions kind of require it. The big issue is if the connection has enough structural strength to survive shifting soil conditions. Normally the deck and the pool are kept isolated so that they can shift separately. This allows small shifts without causing any serious problems (i.e. cracking), but large shifts will create discontinuities in the level of the coping and the deck that become trip hazards. Connecting them together is preferred when very large soil shifts are not just expected but certain. When connected, the connection has to be done correctly or it simply encourages cracking and worse kinds of concrete failure, which can be quite serious.
