The Biology Online definition for "decanalization" was very ambiguous and weak.
Might I suggest the following definition:
"Canalization is the phenotypic robustness, i.e. the ability of a population to produce the same phenotype, regardless of variability in its environment or genotype; decanalization is therefore any force (genetic or environmental) that pushes this trait out of this homeostasis or equilibrium to become less robust, i.e. the organism now exhibits more risk of disease or weakness."