SOUTH PORTLAND — The Knightville Traffic Committee has endorsed a compromise plan to restore two-way traffic to downtown Ocean Street. Yet even committee members who support the plan question whether it would actually work and say they are unable to back it wholeheartedly. The plan would restore a southbound lane to the block between D and E streets by removing six parallel parking spaces from the east side of Ocean Street and replacing 14 angled parking spaces on the west side with 22 perpendicular spaces. The committee considered a second option that would replace the 14 angled spaces with nine parallel spaces, creating a more traditional streetscape that also would restore two-way traffic, but would have parallel parking on both sides and eliminate five spaces on the block. But it was the compromise plan that got the most votes at a recent committee meeting, even though some members remain unconvinced. “I’m skeptical about it,” said Caroline Hendry, a Knightville resident.