Here is some insight on how Hiruzen being able to use all techniques isn't a plot hole.
Hiruzen clearly used an ability that is like what the Bykugan does: telescoping vision across vast distances
So it's entirely possible for him to access KKG abilities via special tools.
He doesn't need special bloodlines since he has the tools.
This supports this fact
Hiruzen clearly used an ability that is like what the Bykugan does: telescoping vision across vast distances
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So it's entirely possible for him to access KKG abilities via special tools.
He doesn't need special bloodlines since he has the tools.
This supports this fact
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