trisket said:
The Spit is quiet, not much scenery. It's closed to the public during weekdays for trucks hauling landfill.
It's nice and isolated for rollerblading or cycling during their off-hours though.
Actually there's plenty of great scenery at the spit.

If you walk in for abit there is a new walkpath that runs along the shoreline that has a great view towards Woobine beach. If you go in abit further and look westward, there a big marina with lots of boats docked there usually and in the background you can see the city skyline.
Also there's a lighthouse there at the far end of the spit, like at the most western point of it where if you go up the small hill you can see the Toronto islands and a awesome view of the city skyline. From that view, the islands look so close to the mainland, it makes you wonder why don't they build a bridge to connect the island to spit so more people can enjoy the islands without having to use the ferry.
As for when its closed, I've biked on weekdays at the spit and see people going in and out of there without any problems. So I'm guessing its just closed during the night and maybe mornings? Because people go in and out of there in the afternoons and evenings without any problems and there doesn't seem to be any traffic going in or out other than the occasional car.