Breakdowns on TGV lines: how can such delays be explained?

On Friday, July 25, numerous trains were delayed departing and arriving at Gare de Lyon in Paris after a power supply failed near Lyon (Rhône).
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It was a crush on Friday evening at Gare de Lyon. Departures and arrivals were up to six hours late. Passengers still hoping to catch their train bumped into those who had finally reached Paris. Like a mother and her children, who spent twelve hours aboard the TGV Inouï from Nice ( Alpes-Maritimes) . "We didn't have anything to eat or drink because there was nothing left in the bar. Everyone was a bit nervous and it was a very complicated journey," she explains.
The cause of these delays was an incident on the high-speed line near Lyon (Rhône). A power supply was struck by lightning around 5 p.m. in Cesseins, in the Ain department. The line was out of service, and trains had to be diverted. TGV trains heading for Paris had an 80 km detour via Villefranche-sur-Saône (Rhône). Those heading for the provinces had to go via Dijon (Côte-d'Or), Chalon (Saône-et-Loire), and Bourg-en-Bresse (Ain), about 200 km on slower lines. Among them, a TGV Ouigo was attempting to reach Paris via rural roads. A few bottles were distributed on board.
But the main complaint among travelers is the lack of information. "It's 9:30 p.m., and we were supposed to arrive in Paris an hour ago. And we don't know what time we'll arrive home because the train is running at two miles an hour. Yet, there are working microphones. They could keep us more informed about what's going on," complains one traveler.
Contacted, the SNCF explained that it had to manage the traffic jams caused by the diverted TGV trains. "Tomorrow, if you have an accident on the motorway, you will simply exit the motorway to go onto the national road and bypass this event. But it's the same, there is already traffic on the national road and so this is added to the existing traffic, and so this is what causes these delays," says Frédéric Guichard, director of operations for the South-East SNCF Réseaux rail network.
SNCF's priority was to get all these trains running. No cancellations, a relief for this traveler: "As long as they tell me the train is leaving, I'll wait. Worst case scenario, I'll sleep in it, and it doesn't matter." Affected travelers will be able to get a refund, at least 25% of the ticket price for delays between 30 minutes and 2 hours, and 50% beyond that, with some more favorable conditions depending on the company.
Francetvinfo