Not sure of the meaning of clenched bottom brackets, but if it is the cotter end cranks, or bolted style, the one piece crank design came in shortly after 1900, as a general rule. Narrow bottom brackets, that the one piece crank could be installed through, with a simple bearing adjustment system were faster and cheaper to build. The pinned cranks have never completely disappeared, nor have the splined with nuts. There have been hundreds of crank and bearing designs over the years, with varying levels of success!
