I would say that in the case of Dirk, Kobe and KG it is 100% safe to say if they had done 1-2 years of college, they would EASILY have been the #1/2 overall picks and that the world has changed greatly since they were drafted. KG and Kobe were the FIRST PLAYERS IN 20 YEARS TO COME RIGHT OUT OF HIGH SCHOOL! Where would they have been drafted after their freshman years? No brainer top 1-2 picks.
Coming out of HS in 1995/96 was seen as far too risky for people to make them high picks, but people know now that its smart to draft HS kids because the best ones adjust quickly. And Dirk coming from Europe was a relative unknown. If any of these guys had done 1-2 years at Kansas, UNC, Duke, wherever, they were sure fire #1/2 overall picks.
You are much less likely to pick off that kind of talent at #5, #10 and #14 again. Why? Because the US kids HAVE to go to college and because the foreign guys are so well scouted now and a great player is not going to be overlooked like that again.
If you take that into account, then you can go back over virtually every NBA champion over the past 25 years and see either one of those 3 guys, MJ or a #1 overall pick on the team. You need a SUPER DUPER star to win in the NBA. There was a small window where you could luck into one of those guys at 10 or 14 (great work by Don Nelson and Jerry West). That's unlikely to ever happen again.
Further, you would see that in the last 30 years, there's been ONE team to win a title without a player who was/would have been picked in the top 3. Most titles are won by #1 picks or guys that WOULD have been #1 picks if in college for one more year.
So:
1. You win with superstars and those superstars come from top picks.
2. You know who those superstars are going to be at a very early age.
3. You can add a million Monta Ellises (is the plural of Ellis "Ellii"?) and Sam Dalemberts and Amare Stoudemires to your team and you won't win a thing.
4. The Celtics are putting themselves in position to grab one of these players.
5. NOW, its true that getting a number one pick IN NO WAY guarantees you a shot at the title. A year where Anthony Bennett is the number one pick is a prime example.
6. BUT ON THE OTHER HAND, sometimes, there is a year with MANY potential superduper stars at the top of the draft, and all indications are that this coming year is one of them.
The logic is straightforward and it is sound. The path isn't guaranteed, but the last time we went down this path, we thought the worst had happened and we ended up contending for SEVEN years and would have won multiple titles if not for KGs knee injury.
The only thing that IS guaranteed is that by pursuing the likes of Ellis, Dalembert and Stoudemire, you are relegating your team to life in NBA purgatory for years to come, with no hope at all.