Count me with the others, here. The cop was wrong to suggest you had to remain on the right or that you should take the sidewalk. Both 814.420 and 814.430 allow bikes to move left in similar situations, and it makes sense to me to take that lane in this case. I like wsbob's suggestion to take the matter to the BBAC; it's a good opportunity to bring city cops up to speed on bike laws.
I say "similar situations" because I do see a little gray area. Looking at streetviews
it looks like there's a left-only lane onto Farmington (TV Hwy 10), and from Simple Nature's description he was actually going just past Farmington to take his left, perhaps into the alley just past the RR tracks? Since the left-most lane is left ONLY, and since S.N. is actually going past the Farmington left, maybe the correct legal place to be is in the center "go straight" lane south of Farmington, moving to the left side of that lane as it becomes the left-most lane as it crosses Farmington. Does that make sense?