It's a shame something like this was never seriously considered since it would address the issues of fixing the SRT, as well as providing rapid transit along Sheppard East (or, at least close to Sheppard East for most of the route, since it would largely run along the 401) as well as rapid transit towards Malvern, for about a fifth of the cost of the SSE, Sheppard Line extension and Eglinton East LRT combined (just guesstimating here, but the three projects will likely wind up costing around $11-12 billion total, as opposed to just over $2 billion for the Scarborough Wye, although I find myself thinking that those estimates were a little low). But any alternate plans are long out the window, at least for the SSE, and there's still plenty of time for an alternate plan to be proposed for the Sheppard corridor, since you never really know what kind of plans they're cooking up at Metrolinx these days, and any shovels in the ground for that project are probably at least a decade away.
It really is a shame that the attitude of transit planning in Toronto these days seems to be strictly subway or LRT (or BRT, if you look further out from the city), with nothing in between. It's ironic that this is the position we're in now, when the entire point of the ICTS technology was to bridge the gap between subway and LRT. At least the technology didn't completely go to waste and now forms most of Vancouver's SkyTrain system.