What is "TSKB 75 ohm" cable? I assume it has 2 conductors + shield?
The twisting is important for balanced lines, like mic cable. The twisting is an attempt to have the two conductors occupy the same physical location so any induced noise will be equal in both conductors. Quad core takes this one step further such that by pairing each conductor and twisting the four together, the "virtual" location of the balanced line can be placed on top of each other. Quad core can have up to a 20 dB greater Common Mode Reduction Ratio (CMRR) vs regular balanced lines. Common mode reduction is more effective at lower frequencies, such as the noise induced by power lines, rather than noise induced by higher frequency RFI.