If those speeds are accurate he made a bigger change than +3 rear. Sounds like he dropped a tooth in front as well. That *will* decrease chain life somewhat as the chain has to make a sharper bend around the smaller sprocket. I'd at least confirm what's on there and go back up on the front if necessary.
KeS
(+3 rear would be about an 8-10% gearing change on most bikes, and your speeds reflect at least twice that amount.)
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