re: Was it Smart and his staff or did the pieces fall into place?

I feel like it was a bit of both. Kirby obviously came in put it all together and is recruiting like gangbusters. That said, because the mainstream UGA discourse, at least on the message boards, has become so vehemently anti-Richt, I think that most people forget that most of last year's great players (Chubb, Michel, Roquan, etc) were Richt's players. Smart has been able to finally not do less with more.
The way we are recruiting, I hope this trend will continue.

ETA: With 2018 being Kirby's third year, a lion's share of this year's starters will be Kirby's recruits. I think that this year we will see that Kirby Smart is not Terry Bowden, winning his first 20 games with Pat Dye's players and then falling off when they all graduate.