Well the title probably got your attention. I'd better explain. Whilst working on a couple of Campagnolo equipped bikes today I was reminded of the number of times I've had to remove Shimano gear cables from a Campy lever. The nipples on Campy gear cables are ever so slightly smaller than on a Shimano/SRAM cable with the result that if you put a Shimano/SRAM gear cable in your lever it is a beggar to get out if you don't know how to do it. This is because the oversized Shimano/SRAM nipple wedges itself fast in the lever. Fortunately Campy levers are easy to work on and I can strip, remove the offending cable and rebuild in less than 10 minutes - I've had plenty of practice!
But who would make such a mistake of fitting a Shimano/SRAM cable in a Campy lever. Any DIY mechanic could be easily be forgiven for making such a mistake but surely a bike shop would never do that?
Whilst in Cumbria a few years ago I was in urgent need of a Campy gear cable and went to a long established bike shop (that sold quality road bikes) and asked for a Campy compatible gear cable. I was offered a Shimano gear cable which I declined repeating that I wanted a Campy compatible cable. "They're both the same". "No they're not, the nipple size is different". "No, they are exactly the same". To avoid further argument I bought the Shimano cable, borrowed a file and filed the nipple down to size!
Hopefully this article shows that, by fitting the right cable now, you can save time and money at the point the cable needs replacing. Bear in mind that some bikes shops are charging £60 an hour for their labour!