Lal, I must acknowledge that before the checking the sutta reference, I too believed logically that it must be true (that vast majority of defilements are removed.)
Your analogy was not exactly 100% misleading or wrong. In addition, I heard similar statement made by waharaka thero in this following sermon. (Which is same as your sand grains analogy. He too said defilements are removed instead of suffering, at least that is what I read in video English transcript.)
Link: Link to English transcript desana by w. Thero
(Statement starts at – 6m:55s)