Capsule pipelines are another pipe dream: If to be implemented on a grand scale, yes.
Successes are in Niche Markets
Capsule pipelines have been successfully applied to a number of niche markets. These markets have either developed from nothing (such as telegraph conveying), with the resulting pipeline network growing with the market; or do not rely on the existence of an extensive network to be successful (such as cash transfer systems within supermarkets and banks). Some of the current proposals for capsule pipelines implicitly acknowledge this, by targeting very specific markets. Unfortunately, however successful they are in their chosen market, they can never have a significant impact on transport in general.
The Network Irony
Like many innovative transport technologies, capsule pipelines could potentially be applied to a much broader range of movements, in competition with modes such as road and rail. These require extensive networks to be put in place to cater for existing diverse movement patterns. In a number of current proposals the requirement for such networks has been minimised by allowing for easy interchange between modes. This dilutes the concept, and almost certainly the impact, but is an obvious concession to reality.
For most modes and localities, construction of effective transport networks requires a vast amount of resources. Historically these networks seem to have been developed in one of two ways - the implication being that these are the only two ways. Some were delivered on a piecemeal basis over a prolonged period, as the markets they served developed. Historically, roads and shipping are examples of this; space transport may be so in the future. Others have resulted from a quirk in the way capital is raised in modern economies. They result from a period of irrational mass investment, based on growing stock market valuation, creating a far greater level of capital than might ordinarily exist. Invariably the long term in-sustainability of this contributes to a crash in the stock market, but not before sufficient infrastructure has been put in place to have allowed the network to operate effectively. Railways are probably the best example of this. Telecommunications / the 'internet revolution' may be an important emerging example.
The irony of the current situation may be that however incredibly efficient a new transport mode might be, in all probability there is no way the economy can resource its full implementation, failing to develop the level of network required for it to be efficient.