The "two lane solution" doesn't work well for cyclists and will create serious enough problems for traffic management, but one of the things it can't do is provide any space for pedestrians. They are sometimes shortcutting down the ramp access for the Ocean Pointe Hotel (and there's another issue - what happens to their access if that inside lane is closed). Peds are chancing gaps in traffic to run across to the sidewalk on the south side of the bridge.
The limited space that might be used for cyclists on a closed travel lane would create serious safety issues for pedestrians if it was assigned a multi-use status. Without robust physical barriers (a real engineering challenge), pedestrians and cyclists could be wandering in and out of heavily used travel lanes to avoid one another, never ideal on the rail bridge or in congested sections of the Goose, but at least mis-steps there have not been into moving traffic.
More of the discussion and an illustration at my flickr photo page: