I’m not so sure about that (speed, that is, not keystrokes). As a matter of fact, I’m inclined to believe that the opposite is true. Touch typing doesn’t work nearly so well for most people once their fingers have to go more than one row of keys above the fingers’ home positions. Because zhuyin has many more zimu than a QWERTY keyboard has Roman letters, people wishing to type using zhuyin have to stretch up to the top row of number keys extremely often, resulting in losses in accuracy and speed.[/quote]
I can only offer my own personal anecdotal evidence as I’m fairly adept at typing in both BPMF and Pinyin. Many moons ago, I took a course in touch typing (in English) as a junior high school student and thus, can type roman characters without much thought. When I first started to type Chinese using BPMF, I adopted the ETEN keyboard layout because there’s a good correlation between the sounds of BMPF and the roman characters. As with anything, typing speeds improve with time and over time, my BPMF typing has become a lot faster than Pinyin input.
I’ve mentioned this elsewhere but I’ll restate some of the advantages to BPMF typing. First, there’s fewer keystrokes per character as already indicated. Second, the order of entry of BMPF is unimportant. This is a big time saver because a very common mistake when typing fast is not that the wrong keys were hit, but that they were hit in the wrong order. Thus, “jiang” typed fast may very well end up being “jaing” and you gotta start over. In BPMF, this isn’t an issue. ㄐㄧㄤ can be typed as ㄧㄤㄐ and it still works. The correct sounding character is still displayed. This offers a unique advantage of hitting keys simultaneously. Let’s take “sang” for example. In Pinyin, it necessarily requires four keystrokes in the correct order. In BMPF, since order does not matter, I can hit ㄙ and ㄤ simultaneously, reducing the typing time to effectively one keystroke. Whether it ends up being ㄙㄤ or ㄤㄙ is irrelevant.
This should more than make up for any speed reduction by having to type using four rows. Besides, I’ve never had much of a problem with four rows. Once you practice something enough times, it becomes second nature. For English typists, the numbers row is usually hard to use not due the lack of innate ability, but rather the lack of practice as there is rarely a need to move your fingers up there. But take a look at professional typists and you can see that these ladies (mostly ladies) type the top row just as effortlessly as the bottom three.