I remember that, but there was a follow-up a couple of years later. Later they put the plane in a wind tunnel and found that the bolt heads were where there was no drag, so there was no problem having bolt heads in those locations. As such, it was an elegant solution to keeping costs down with no loss of performance.
I had the opportunity to talk to a aeronautic engineer who was very well versed on the tests they did. He thought that the plane was engineered to work despite quality control issues. Which in his opinion was quite a feat unto itself.
interesting....as I understand, the Soviet military was designed for 10 day war +/- hence ships, tanks, truck and aircraft engines were capable full power for 10 days and then died