It is not always the sideways movement that is discovered, as stated on previous occasions. When taking the Bearing Assembly apart, the Ball at the Thrust Interface, usually discovered to be a loose fit, or interference fit in the base of the Platter Spindle are on occasion found to be damaged with a Spalling and even worse a Scribing on the Ball Surface.
Either one of these being present is an indicator for Metal Particulate being free to migrate and is now included in the surfaces where there are interfaces between Sacrificial and Non-Sacrificial Materials.
Such an environment has the capability to cause unwanted damage to the non-sacrificial material.
It is an even worse condition when the housing is arid dry in relation to lubricant, loose and migrating metal particulate damage in this type of environment will need substantial skills to correct the damages being witnessed.
Again, it is each to their own, if the want of an individual is to use a $2K to $5K Cart' on TT, knowing it has such a condition, or potentially has such a condition, then that for me is just fine.