I don't know for sure, but would suspect that a major stressor occurring at just the right time might delay a shed rather than trigger it. It takes a while for the old shed to loosen off the new skin forming underneath, so a stressor might inhibit the normal process. But if the process was past a certain point it might not make any difference...when the time comes, they would shed regardless of being shipped. Yes, chams shed more often when young because of their faster growth rate. Also, when they are mature and have fully grown horns, spines, crests, casques that are less flexible, these areas tend to shed less easily.