You keep it in one pieces because you want to keep all the moisture inside. It also needs to roast a long time to get soft. Shredding it beforehand would make it tough I think.
It's in the oven to rest. Never cut into beef/pork straight away after grilling. All the juices will just flow out. It needs to settle. The longer the roast the more time it needs to rest.
Smoke adds flavour to the meat indeed.