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[OngBonga]

Ok so I think I know why h-bar and not h

It's the uncertainty principle. It's the limit at which we can have certainty of the location of a particle. To locate it any further would give rise to potentially infinite momentum. h-bar seems to be the point at which this infinity is reached.

[MadMojoMonkey]

Ok so I think I know why h-bar and not h

It's the uncertainty principle. It's the limit at which we can have certainty of the location of a particle. To locate it any further would give rise to potentially infinite momentum. h-bar seems to be the point at which this infinity is reached.

There's nothing wrong with reducing the uncertainty in either 1 of the terms on the LHS of the inequality, provided the uncertainty in the other value is of no concern to you.
This principle is what allows the LIGO to work. They're measuring length changes many orders of magnitude less than the diameter of a proton. Which can only be done if you don't care at all about the uncertainty in the momentum being arbitrarily large.

The universe tends to put a kibash on infinities. Conservation Laws are very effective at preventing any system or object from gaining infinite energy or momentum or a few other properties. The requirement to inject infinite X to the particle or system requires something else lost infinite X (provided X is conserved). The lack of an infinite to lose prevents the rise of anything else to infinite.