That's exactly where the problem lies. You can make GO trains 20 cars long, micro manage track time, or add an extra track here and there, but these are just short term, ad hoc solutions.
Solutions that are going to have a long term, valueable impact, such as reconfiguration and dedicated tracks on the Lakeshore line and Weston line, electrification, buying and expediting land for new lanes, etc, is going to be expensive. And not only is it expensive, but it lacks political selling appeal. A new subway line is costly, but after you spend a billion dollars you have new stations, new trains, something very tangible. If you spend the same amount of money upgrading Lakeshore, there is no new product for photo-ops.
What I find most frustrating is that passenger rail could be a huge success if it were given the chance. While the past 50 years have essentially belonged to the automobile, rail travel is still a part of Canadian culture. VIA remains to be successful in the Quebec-Windsor corridor despite all its problems. AMT and GO continue to grow despite limitations. Companies such as Bombardier and CN do hold a certain amount of nationalist pride. Another thread on this forum has shown that cities and communities do desire and would like better rail access, and in some cases such as Masscouche in Quebec, have been successful in influencing decisions for rail expansion.
Returning to the comparison between highways though, passenger rail lacks the dedicated infrastructure it needs to be successful. Car and truck transport would never have exploded were it not for the freeway. No difference with rail. European rail systems are a good example of this. While higher densities do mean more service can be supported, it is the dedicated infrastructure nonetheless that makes it possible to offer such efficient and varied service.
In the short term, I don't see a lot happening in terms of large scale investment in rail travel though. There is still too much of a gap between the current situation and where it needs to stand for real progress to take place.
On one hand, there needs to be the political will to do so. High speed rail has been suggested a few times by the federal government and examined to a certain degree so the idea is not totally new. But its going to take a federal government alongside provincial governments with a willingness to actually put forward the money required and develop a plan for large scale investment. At best we have governments that want to dismantle VIA, which would not be a bad thing if it ment handing it over to provinces for example and not just gutting it wholesale.
On the other hand there also needs to be a strong expressed desire by a large number of citizens or groups. Its encouraging to see that Kitchener is speaking up about wanting better rail service. That is only one voice however and will no doubt be drowned out by the calls for more expressways for the time being. What needs to happen is for a coalition of forces to speak up and make these demands. When Barrie, Peterborough, Hamilton, Niagra Falls, Kitchener, community groups such as the Weston Coalition, and others, all speak with a single voice, then you will see action begun to be taken on the issue.
I'll end this rant by saying that in many ways, the Quebec-Windsor region is in a rather ideal position. You have a growing demand for rail service, denser, more urban development being constructed (which will be better suited for transit service) and rising oil prices. With all these, and other, factors put together, slowly you have an environment (physical and economic) being built that means passenger rail will become a much more viable option in the near future. But it is also happening at a rate slow enough that trends can be observed and thoughtful planning can be done (as opposed to being caught off guard and rushing to come up with quick solutions). It might be 10 or 15 years before we see large scale projects such as upgrading the Lakeshore line or dedicated tracks between Montreal and Toronto. Thats not entirely bad given the amount of work that would be invloved before shovels ever hit the ground (land aquisition, EA's, public consultation, financing, etc all take a fair amount of time and for large scale projects it is not uncommon for these processes to span over a decade). It might seem frustratingly slow at times, but at least the wheels are in motion for large changes to take place and to some degree, it is this period where plans and ideas are being created and proposed that is the most interesting.