Puzzle #572 - Pairs (Slitherlink)

Lately, djmathman has been making some large Nikoli-style Slitherlink puzzles. I decided to try to make a puzzle that had a bit more flow and a bit less bite to it than my usual puzzles, and what easier starting point is there than a 33 in a corner? The rest of the puzzle made itself, though I did tweak it several times to reduce the difficulty of the middle and emphasize a logically flowing theme throughout.

puzz.link interface