|Take it in, I'll wait|
The sacrifice of time was worth it.
There is a common myth that QWERTY, the layout just about everyone in North America uses, was made to slow down fast typists, but fast typists didn't really exist at the time. There were no known or well taught typing techniques, and touch typing wasn't even an idea yet. Plenty of people today prove that QWERTY isn't a slow man's layout. QWERTY was invented in a time of necessity. Early typewriters jammed easily. QWERTY didn't eliminate this problem, but jamming was greatly alleviated. Dvorak's layout came many years later.
In 1936, Augustus Dvorak introduced his collaborated simplified keyboard layout, simply known as Dvorak today. Fifty years before, such a layout was unthinkable. Frequently used keys are too close together, increasing the risk of typewriter levers and hammers running into each other and causing frequent jams. Technology solved this in ways that QWERTY never could and Dvorak decided that then was the time for change. Dvorak, and the German army, claimed that the layout was easier to learn, produced faster typists, and solved ergonomic issues. Bold claims, made on shaky ground, but the ergonomic advantage is hard to argue against.
Dvorak did his own studies, which were monitored by the German Army. Augustus Dvorak was in the German Army. These few facts, as well as the little documentation of the studies, bring to light suspicion of Dvorak. There have only been a few studies, and they've all claimed different things. One by the US Government claimed that Dvorak took longer to learn, and typists were at higher speeds sooner on QWERTY. This study is probably what kept Dvorak from hitting the mainstream. Both studies lack any rigor, and many claims on either side are somewhat unsubstantiated.
I'll stand that Dvorak is better from an ergonomic perspective, but it is very sophomoric in its approach. Today, Dvorak doesn't hold a candle to modern layouts like Workman, Colemak, Norman, Asset, or just about anything else. Dvorak was made for a typewriter. Colemak is made for computers. Most newer layouts take after Colemak, preserving some of QWERTY's layout, and keeping ZXCV in the same place, for easy shortcuts, even though they have better placements.
The advantages of these layouts are many, but they're all very hard to explain, and some are even hard to conceptualize. Even their flaws are hard to understand. Today, like 80 years ago, there is no good study or rigor of testing. There is also no by-the-numbers solution to a keyboard layout. The deeper we dig into ergonomics, the more assumptions we make about what's best and how to make things more efficient. Many even argue that there really isn't anything wrong with QWERTY, but we know those people are wrong.