Eh, I never LSP glass and couldn`t care less if my glass beads or not so I wouldn`t/don`t do it either. But then I do my glass very frequently even though my vehicles are all garaged and basically pampered. Doubt I ever go a week without cleaning at least the windshield and might do it daily. But that`s just me...if you don`t care, and if your vision isn`t compromised, then why bother?
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No question, those areas can be a challenge to do, takes some time and effort. That said, I can`t imagine why you`d get LSP on surfaces where you don`t want it nor why there would be any "wearing down of the paint". Some vehicles are more prone to rust than others, but IME keeping everything clean and well-LSPed helps to significantly minimize that; note that my vehicles are OK in this regard despite being pretty old and subjected to Ohio winters. Yeah, doing some stuff can take a *LONG* time but IME it doesn`t need done very often.
I only applied on glass to prevent water marks/spots. It does absolutely nothing, they still appear. Only drying properly prevents water marks.
Applying this sealant in door jams always gets some in the tight gaps where the metal of door skin folds. It`s hard to remove & constant wiping away will probably wear down clear coat there. Some areas it looks pretty thin, ya know factory paint jobs.