Superbowl

I think it's often to distinguish between two words that would otherwise be homophones.

There's "wick'ed" (two syllables) as in "something wicked this way comes" and "wicked" (one syllable) as in "Grady wicked away the spilled avocaat from Jack Torrence's jacket with a towel".

There's "dogg'ed" (two syllables) as in "dogged perseverance", but also "dogged" (one syllable) as in "Javert dogged Valjean for many years".

I don't have one for "curved" though. I think i've only ever heard it as one syllable, except for maybe in cases where poetic meter requires use of an "èd". Although, I think "curv'ed'ly" has three syllables, but I might be making that up. Typing up this comment has given me semantic satiation.

But, yeah, I think you're right about the adjective vs verb thing. The two-syllable examples are adjectives, while the one-syllable examples are verbs. Except for curved...