That is 100% incorrect. All of the 340 cams were split duration cams. Had more than one 340 cam degreed and cam doctored and NONE of them were ever those lift specs.
My 2 cents it was written that way to sell more purple cams.
The 340 4 speed cam was the 340 auto exh lobe moved to intake side and a 440 mag int lobe set used for exhaust.