What do you average if you use the standard 15 second inspection?
I would suggest to time your inspections, and lowering it second by second. You can try to, say, inspect in 24 seconds, and force yourself to start solving when the timer reaches 24 seconds. If this doesn't affect your times, then continue lowering the inspection time second by second, until your solving times start to get slower. Now you can just do lots of solves with that amount of inspection time that you're having trouble with.