I have definitely had way more problems with cable drag leading to shifting issues on SRAM than on Shimano. Especially on my cross bike where I tend to get mud and grit into the cable housings. Regular maintenance helps. This video demonstrates the technique on a mtn bike, but it works the same on a road bike.
Try that, it may make a huge difference. And I'd say, making this procedure part of regular maintenance, especially after wet rides, will help save your SRAM system from failure. I've managed to break two shifters due to leaving cable drag too long.