I am similarly picky about most or all of the examples mentioned, plus several others: 'sickth' (not sixth), 'lore and order', drorings, etc. Regarding the Off-of, this originated in the US (along with 'the thing is-is...', etc.) and I understand it is at least partly due to influence from other languages (the immigrant mix). German very nearly became the official language in the US but narrowly lost out in a referendum - there 'ab von' inverably go together and mean off (of or from - other languages have something similar).