It's interesting to note that 45s almost didn't survive the mid-50s. They were originally an early-1940s idea dusted off by RCA during a corporate war with CBS in the era 1945-1950 which included radio network talent raids by Bill Paley at CBS and rival color TV systems. 45 sales had dropped badly through about 1955, and in 1957 the Crescent Industries factory in Chicago burned down - that was the company that produced almost all the RCA 45-only changers. With stereo coming in, RCA was actually considering dumping the 45 single. Rock n' roll and Top-40 radio saved it!
And the hits just keep on comin'! I agree with the barrister of the board, Motown 45s were well-pressed and it seems Stevie Wonder 45s were pristine. Rare Earth was another Motown subsidy that wore well. Capital 45s, primarily those with the ugly orange/red/black logo and speed bumps, but also those with the classic yellow/orange swirl, survived repeated cue-ing. WYSL Buffalo used quick-start 12" QRK turntables, with an ingenious upgrade: The felt was removed and in its place, canvas. No felt build-up in the grooves. Styli seemed to last longer. Seems any 45s in my collection from WYSL Buffalo have very little q-burn. There was little need for most of the 1400 Boss Jocks to slip-q 45s or LPs because those turntables came up to speed so quickly, about an eighth or sixteenth of a turn.
As Savage has recounted, the 16" RCA turntables at KB were archaic. Only the back turntable had a remote start, a mercury rocker switch that looked like it was shade-tree engineered on the countertop to the right of the RCA board. Heaven help you if you accidentally brushed over it while moving a cart or the copy book.
But overnight guys who ran their own board could make the 16" RCA tables sound tight without having to resort to slip cue-ing. It took some practice and forethought. Besides, it was a pain to slip-cue a 45 on a 16" turntable. The flip side of those felt turntable pads were cork. Never used the cork side. KB's combo/jock studio at 1430 Main Street had 12" QRKs after NABET compromised and allowed the jocks to run their own board and music (through a new but clunky McMartin board) while engineers ran master control and all content on tape and carts through the classic RCA board.
Later, KB became all combo using a spiffy McCurdy board and snazzy Technics instant start direct drive turntables when the NABET engineers agreed to a contract that provided job security in exchange for attrition. After that, all music was played off ScotchCarts. Gummy labels, worn pressure pads and rattling metal tension bars not included.