Huh, most of the words pairs you listed have extremely distinct consonant differences, but not very distinct vowel length to my ear (which is pretty influenced

Huh, most of the words pairs you listed have extremely distinct consonant differences, but not very distinct vowel length to my ear (which is pretty influenced by southern appalachian english). Ie, "loose" is a "s" sound, and "lose" is a "z" sound, "ck" is much harder than "g", same with "f" vs "v" and "d" vs "t". None of those words sound awkward when shortened to me, they just sounded like they were being spoken faster for some reason (for emphasis or pacing reasons). So I wouldn't consider those different due to simple vowel length differences, but due to core phoneme differences. I do see that the people in that thread who combine "muck" and "mug" are from New England, so maybe those are specific to that accent. There are words which I do pronounce the "same" as each other - but do actually vary them on on length alone. These are mostly for "merged" words. Ie: "Mary" - longer sound on the "a" vowel than the "ry" sound "Merry" - longer sound is the "ry" sound "Marry" - is said like "Mary" except the "a" sound is even longer. "ry" sound is same length. Part of me also wonders if the southern "drawl", where vowel sounds are extended, is actually a weird way of standardizing vowel length times across distinct phonemes. Though I wouldn't be surprised if there's still variation there too, but it would certainly be interesting to compare.