is leapfrogging real?

as much as I love the concept of leapfrogging, there are those who say it’s basically a myth. 

over several things i have read, the doubts are there.  and they make some good points.  without particular writing style or priority, below are some of the points made by these articles:

• industrial countries have already picked the low-hanging fruit (provided basic social high-return projects like sanitation, education, etc).  only after this have we gone on to emerging technologies (risky and expensive with less social value returned).  leaving the first step undone to invest larger sums of money in lower-return investments doesn’t make sense.
• if older, simpler techs are not maintained (which they generally are not), it is less likely more advanced ones will be.
• more advanced tech has more complexity to manage and needs more resources (policy, tech knowledge, etc.) – better for developing countries to wait and let industrial countries iron out problems and drive down costs first.
• most leapfrog examples have not yet led to widespread adoption or transformation.
• there may be resistance built into the situation – old government mandates, cultural incompatibility, lack of coordinated progress forward, dearth of educated/qualified people to sustain it.
• literacy is required for many new techs (unlike cell phones).
• walk before you crawl – many new techs rely on the intermediate or basic techs that came before them ($100 laptops without electricity, advanced systems without solid education system, advanced medical devices without basic sanitation and disease prevention).  would money not be better spent on teacher training and basic infrastructure?  tech is more glamorous, but electrical grids, sewer systems, transportation, safe water, schools are more important to raise the level of the people living there.
• World Bank data indicate early adopters lead to tech diffusion fairly reliably in developed countries, but do not do so in poorer countries.  although technology is spreading to emerging markets faster than it ever has before (think of the spread of railways  (120 years) vs. radio/tv (60 years) vs. computers/cell phones (16-20 years)), the rate of diffusion among the overall population is stunted. 
• in china and india, the World Bank found that while cell phone usage is expanding, so is land line installation.  the pattern, it seems, is that cell phones are leading the patterns of communication where land lines then get laid.
• most examples of solar or internet leapfrogging are isolated, pilot experiments.
• one article draws the distinction between infrastructure (being developmental -- requiring the building of middle technologies to support new initiatives) and gadgets (being ecological -- able to jump earlier tech).

still, despite the preceding, I like the leapfrogging idea.

is leapfrogging a myth?  i don't know.  it's certainly a compelling concept. i think that leapfrogging tech for the sake of technology and convenience is of secondary importance to core societal needs.  but leapfrogging in that realm (solar power, clean water, health impacts) can transform life.