The goal is to be able to set your chain so it never gets too tight when the suspension compresses.
That is because as the suspension compresses and the swingarm brings the front sprocket, the swingarm pivot, and rear sprocket into line, the chain gets tighter. When all three are in direct alignment, the chain is at its tightest point.
That is why I take the few minutes it takes to put the bike on the center stand and do the following:
1. remove the bolt that goes through the bottom of the dogbones so the swingarm moves freely.
2. block the swingarm up so the chain is at its tightest point (sprockets and swingarm pivot in line).
3. adjust chain so there is no slack but it is not too tight
4. align wheel, double-check chain tension, and tighten everything
5. remove block holding swingarm up and replace bolt and nut at bottom of dog bones
It took me longer to type this than to do a chain adjustment as described above. It sounds like more work than it is.
The big payoff is in knowing your chain is adjusted adsolutely correctly.
Then you will see that the results will be pretty close to what you get by using the technique described in the factory manual - that is, if you do it exactly right.
Better safe than sorry. Take the time and adjust it correctly. If you keep it clean and oiled it will last a long time between needing adjustments.
Hope this helps.
Dave