Breath of the Wild - Difference between a Good and Bad Slew
If at first, you fail miserably, it's likely not because you suck at the timing, but that you just have a bad slew.
I got my slews from a tree in the first Sword Trial, both good and bad, rather than from the Shrine by the Deku Tree. I seemed to keep getting bad slews from that and it got tiring thinking I had to re-load the save just to try to get another slew. I experimented and now I have a reasonable method for attempting new slew angles.
A really good slew will have Link (or in my case Linkle) angle enough to almost move out of frame. It should also be noted that the sound of the Shield doesn't matter, you can still obtain a slew without the sound (and in a previous attempt, having Link face-plant against the tree).
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