4.2.4 Adaptability and Usability
The importance of consistency appeared to be literally central in relationship to
other concerns in the technical context of all projects. It was arrived at for a
variety of reasons and resulted in a variety of benefits.
Consistency was a global characteristic of courseware that contributed to the
achievement of usability, although it was sometimes arrived at for pragmatic
concerns for adaptability. ESCAPE developer's discovered "usability" benefits
in the process of gaining adaptability. These gains included an improved user
interface through the higher consistency required. The underlying cause of the
relationship between usability and adaptability was explained in a conversation
between Tillotson and Hopper (personal interview, June 23, 1992), where they
describe that by seeking portability and the ensuing process of dealing with
the need for consistency in the data, a much more powerful, and usable interface
was produced.
Hopper: Is it your intuition that some of the things we've discovered
for good programming purposes are good for user interfaces as well.
Tillotson: Consistency is perhaps the most important issue in a system such as this.
A clean system design not only helps the developer, but it also helps the user to work
with it more efficiently.
Hopper: So the flexibility allowed by HyperCard may not be as beautiful in a lot of ways.
The freedom it allowed didn't create better materials.
Tillotson: Freedom is only good in hands of someone who knows how to use it.
It is also freedom for someone who doesn't know what they are doing to hang themselves.
(Tillotson & Hopper, 1992 )