The reason for all the record keeping is to show even the better league bowlers aren't consistent enough to justify such minor changes. The THS allows bowlers to not have to be accurate and that's good because most aren't. If you are leaving 10-pins, the THS provides the bowler with the means to make substantial adjustments and also be able to improve carry. You don't have to nickel and dime the adjustments.
If we are talking about sport shots I still doubt the effectiveness of making such minor adjustments forward and backward on the approach. But if you can hit half boards at the breakpoint and control your speed within one-tenth of a mph, then go ahead and make those moves. I really would like to see a digitrax of these movements.