covering exhaust or stack on equipment ?

I was told this several times over the years. 1 of my mechanic instructors even swore up and down that every new piece of equipment they got at the dealer he worked for had turbo failures within 6 months. Once they covered the exhaust in transport it apparently stopped. Now in my personal experience I have yet to see it happen. We have a very large fleet of equipment and I have only seen 2 or 3 turbos get changed out in the last 2 years (exhaust wide open during transport, usually less than 100 km 1 way) Based on my personal experience I'd say its very unlikely it would happen but I wouldn't want to be hung for the cost of a turbo replacement that could potentially be avoided by 5 extra minutes of work.