I believe it is very basic. And a restriction beyond one degree of freedom at this location, given the "real estate" available, and that the likely loads that would soon lead to failure likely due to fatigue with more joint restrictions. while proving that there is loading here and its significant. But you can't include a solution that you know will fail, so you don't tackle the problem until you can. Yes the spherical joint connection is only an improvement, but certainly not a cure all.
I've seen many Monte Carlo bars with spherical ends strangely.
