Agreed. You must work with your cue/shaft and determine what if any systematic type adjustments can be used as a guideline to offsetting the various effects when using spin.
For instance, I have 2 or 3 different methods I might use depending on the shot - distance, speed or spin being used, etc. These are guildelines, but because I've worked with them and my own personal shooting style and shaft they are pretty accurate. Feel comes into play as well the more you experiment with english, but the FHE/BHE concepts are a great start.
Try setting up some standard shots where english is required - cutting a ball and spinning one rail with outside, spinning 2 rails with outside back through the center of table, 2 or 3 rails with inside back to center of table, etc. Try using no adjustment, FHE, BHE, or a combination of both. Try the same with soft-medium speed and firm speed. Try the same with 1/2 tip of english, half way out on the ball (1 1/2 tips), and maximum english. You will start to develop a good feel for your stroke and shaft and will see what works when.
Scott