Rim damaged in curb scrape, keep using or replace?
A rider in my Tuesday evening group impacted a curb with a glancing blow, fell down (with no injury), but discovered his rim had been gouged out in the area in the rim brake contact zone, as though a chip about an inch long and maybe a 1 mm deep had been scraped out.
I thought it to be a significant stress riser in the rim and would lead to a speedy cracking failure, and told the guy he should replace it after that ride, which had another 7 miles to go. I also suggested he slow down in case the rim did crack he wouldn't go over the handlebars - as hard. He made it back following the A pack going pretty fast, as much as 25 mph in a few places, and thinks probably it will be ok and he can continue riding.
Am I right - he's risking his life, or is he right - he can keep running with little chance of a disaster?
It's a 26" mtb rim x about 27mm wide, aluminum, probably the same 25 years old the bike is. Is being super cheap with equipment expenditures a good excuse to take risks like that, or am I just paranoid?