If the focus routine always moves to final position in the same direction then oversizing the backlash steps when reversing basically makes it a do not care because the backlash cancel's out.

Think about it this way, currently at 500 with actual backlash = 25
Move back 200 physically moves it to 325 (175 = 200 - 25 backlash), counter though shows 300
Move forward 200 (physically moves 175 = 200 -25 backlash) up to 500 physical and counter shows 500

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