Can You Switch Careers Without Taking a Pay Cut?

According to a survey in the Economist, 13 percent of Americans have taken a pay cut this recession. American workers are making sacrifices to keep their jobs and compromising during the job hunt. The Wall Street Journal has been tracking eleven laid-off MBAs as they search for work again. Within that sample, many had found work but five took pay cuts of as much as 80% while at least three took cuts exceeded 35%.
Penelope Trunk, a career blogger and consultant, claims that recession or not, you simply cannot change careers without taking a pay cut. To those who manage to keep their salaries while switching, Trunk replies:

I think people who make career changes without pay cuts actually do both careers at the same time in some capacity, for a while. In that case, the cost--the pay cut--is really your time: all the other things you did not do while you did both careers.