My experience has apparently been quite different than yours with respect to bearings.
I don’t clean new ones, on that I think we agree, but on the rest of this post, I would absolutely disagree.
You put a lot of faith in the manufacturing process of these bearings. These are not handmade, boutique level items. They are made in large quantities in factories overseas. They are made to tolerances and standards but to say that they are lubed with some magic oil I think is not accurate. They are likely lubed with some generic bearing oil, not a special wizard concoction.
That being said, every bearing I have ever used has been cleaned by me with positive results in nearly every case. All bearings pick up dust, dirt, string debris, etc. it’s the nature of the beast. These bearings are not “sealed” they are shielded. Sealed bearings so exist but they are identified by some sort of not easily removable rubber seal. The ones typically used in this application have shields, not seals. The shield is not watertight or airtight nor is it meant to be. It’s meant to be the cheapest way to keep large pieces of debris from clogging the race and preventing the smooth spinning of the bearings. There are gaps in the shield, most noticeable near the inner diameter where the bearing sits on the post. These gaps do allow foreign matter/debris to get in. As a result, they all require some level of maintenance/cleaning at some point in the life of the bearing. It does not mean the bearing is of low quality in and of itself.
When one of my bearings begins to feel gritty or gets noisy or simply doesn’t seem to spin as long as I feel it should, I de-shield it and drop it in a mineral spirit bath. This removes any oils and washes away any debris. For 1A I simply spin it and blow it out then re-install, dry. These bearings are not subject to much in the way of mechanical or thermal stresses and I have found they don’t need lube for this style. I do add a drop of lube in bearings for responsive throws as I feel it makes the response more predictable.
We will obviously disagree on this, but your post was worded in such a know-it-all way, especially the part where you say it’s the worst thing you can do to clean a “precision” bearing, I felt the need to post a different perspective.
If you are comfortable simply replacing bearings at the first sign of trouble, that is your prerogative. However, it is inaccurate to say that cleaning bearings is not helpful to the performance of the bearings.
Enjoy the throw my friends
kgb