Aeschleman and Higgins (1982) reported no significant differences in trials to criterion between stimulus fading, progressive time delay, and
trial and error. Error correction had fewer trials followed by progressive delay, and finally, stimulus fading had the most trials in the McGee and McCoy (1981) investigation.
Profile dies, however, are still mainly designed by
trial and error using methods that have changed little over the past 40 years.
Boris Lukezic, Amcan engineering manager, estimated that the company would have had 3% scrap due to porosity if it followed traditional
trial and error methods.
For most of the history of rubber as an engineering material, its applications have largely been developed by
trial and error. Prototypes are made for testing, results of which are used to alter designs, as modified prototypes are further tested until acceptable products emerge.
It was unrealistic to attempt this by
trial and error. We would have had to make a small change to the tool, set it in the press, run a few samples to see the effect, then repeat the process until we got it right.
There's no room left today for tedious and time-consuming
trial and error," Perdikoulias says.