Aye but there's the rub. It all depends on how you define "best team", as does a "best team" really exist. What every team does do, Spurs included, is buy to the best of their ability given their funds. Question is how you acquire said funds? I think we can all see that the real days of measured progress over time, success breeding success, are pretty much over given the change in the way the game is financed. Totally different from how it was 20 years ago.
If the modern trend continues, then continual foreign investment will increase the gulf (no pun intended) between the "have" and "have nots". Utd fans may argue that they have built a team without this kind of financial influence and maybe this is the case; but they were advantaged in that as a club they were in European competition at the highest level before this trend started, with all the inherent benefits that had (more money, better world wide recognition, kudos as regards attracting players).
For clubs like ours those days are pretty much gone. Imagine you were a fan of another top 5-7 club from the last couple of seasons. Whereas the last European places were routinely competed for, the number of places will diminish as more clubs buy into the top spots resulting is less time "other clubs" in European competition and therefore less funds and so on.
As Spurs fans we were lucky enough to play CL footy before the Man City changes really kicked in, coinciding with Liverpool failing to achieve to "their expectations" and this allowed us to hold our own better than some others in the EPL, but over time that will change and the result will see a backward step not due to our desire or quality on the pitch, but the comparative quality of our squad and the simply inability to hold on to those players we value and buy those that can improve us. I think we have already seen this over the last couple of years with the eternal striker search.
If we want to return English football to proper competition then I believe that the only way is Ensil's prophesy of the new "Europe League" the EPL of Europe and a return to a consolidated FA league structure. However of course then the problem is that one of the factors that has made the EPL so successful will be lost in the same way that many see the Europa / Champions Leagues or League / FA Cups.
As for me, I don't know which I'd prefer.