+1. As the effect is small, a sloppy adjustment is not a good test of whether it's important. Instead, try this: Adjust the cones so that they are smooth with no play. Then hold the wheel with your hands and allow it to rock back and forth to a stop just by the weight of valve or reflector. Now clamp in the bike and try the same thing. You will find that the wheel stops significantly faster when clamped.
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There's no such thing as a routine repair.
Don't tell me what "should" be - either it is, it isn't, or do something about it.
If you think I'm being blunt take it as a compliment - if I thought you were too weak to handle the truth or a strong opinion I would not bother.
Please respect others by taking the time to post clearly so we can answer quickly. All lowercase and multiple typos makes for a hard read. Thanks!