Please confirm what this is supposed to do. The JB at Dundas / Hyde Park Gate already prevents a U turn, for example. (On the WB403 ramp, I could possibly see the benefit.)
If you’re talking about the EB off-ramp, with the JB already added just for Dundas & Vega/Hyde Park intersection, it is just to give the far lanes for people wanting to go left or right at the next intersection to the east, that’s all. (As described in the screenshot example above.)
I’ve seen one example used here too.
As far as I know, there will be the ability to overlap JB & paths coming soon. But as of now, this is the best setup I could offer.