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Young oil paint is amazingly resilient and tough. Old paint films which have become embrittled are likely to crack and fall off the support when subjected to radical stresses.
Painting on stretched canvas is a relatively "chancey" proposition over the long haul, because the support is inherently flexible, and ultimately, the paint will not be. To avoid grief over sagging, slack, or puckering canvases, the best "fix" is for the painter to be knowledgeable on the properties of painting supports - it's hard to beat painting on your own supports if you have the skill and the time to make them.
In short, the most commonly used materials are quite given to "slacking off". Cotton canvas is not particularly strong, and will often become slack simply from the attack of being painted on. This is less of a problem for a glue-sized/oil primed canvas than for one primed with acrylic gesso which does not effectively shrink the fabric, and remains flexible.
Linen is a stronger fiber, but subject to changes in ambient humidity; slacking off in damp weather and tightening up in dry weather.
Hemp is much stronger than linen, does not get loose when worked on, as cotton does, and is much more resistant to changes in humidty, but it is not commonly offered pre-primed or pre-stretched.
Polyester is eminently stable, stronger than natural fibers, unaffected by humidity, and can be painted on directly without sizing or priming, but there is no "old world mystique" to using it.
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