You know I'd take that argument if it was just one league title, in fact it would be a very valid argument, but he won two back to back bundesliga titles. Also, no matter what you think about the Bundesliga, you still have to beat Bayern over a 34 game season to win it, that in itself is a massive achievement.
I don't think its fair to compare him to Allegri, he hasn't had the chance to manage a team like Juventus. I think its a very different kind of challenge though, when you coach a team that is expected to win, so I don't know how Klopp would do in those kind of settings, but until then its difficult to compare them.
In Klopps defense though I will say that if he reaches the CL final this season, he'll have reached two CL finals, just like Allegri.
Not necessarily. Thats what I'm trying to argue. Everyone knows how Klopps teams are going to play, it doesn't mean you'll know how to stop it though. Thats why tactical flexibility IMO is a vastly overrated trait when it comes to managers. Pep knows how Klopp is going to play everytime, Pep is also a coach that has a brilliant record against a lot of very good managers, yet even he hasn't been able to come up with a way to consistently counter Klopps teams even when the latter's teams have been mostly inferior.
Even in football, when Robben has the ball on the right wing, most of the time you know exactly what he's going to do, he's one of the most predictable players ever. It doesn't mean you can stop him though, as many fullbacks have found out.
In all cases, we can debate this until we're blue in the face, but at the end of the day whether he's a one trick pony or not, the one thing we can't deny, is that he has overachieved with Dortmund and he looks like he's going to do the same with Pool regardless of what his strengthes and weaknesses are as a coach.