Does DL one have free wifi or internet computer? I know president's club has free wifi. I guess as SE I should be using DL?

Last I checked, no free internet at DL lounge. Just T-Mobile.

Simple - the T3 to T1 shuttle often takes way longer than the walk does. The T3 to INT shuttle is far faster (and there is more demand on it by UA pax then UA pax transferring to US or AC).

Sitting in the RCC in T3 now (now that AC has moved to T3)... not a bad location and you can see the two AC gates on the field so you know when you inbound has arrived. The trick is do not listen to anyone who tells you to go through security (the lounge is past security) at the UA gates... the lines are too long... go through the AC/AA security - the *A gold line is always short and then a short hop down to gate 76. The walk from gate 76 to the AC gates is not intolerable and maybe takes 5 minutes at most.