[emn13]

The fact that they go on disk is a pro, not a con; and the fact that they're one character not multiple is also a pro and a not a con: what's the point of the individual characters? Those were merely introduces as a necessary workaround to cope with input limitations. Kind of like C trigraphs - and nobody uses those because they want to.

[MrQuincle]

Unicode is a disadvantage for someone who wants to contribute to your code. That person now has to figure out how to write down Unicode arrows, taking her/him out of her/his flow.

[kps]

Sure, and the Dane has to figure out how to write down ø, taking them out of their flow — until they learn to apply the correct tool for the job.

[MrQuincle]

I'm not sure if you're sarcastic or not. However, I'm Dutch, and we have similar tokens.

Nobody minds if you write Danish code, but if you like contributors, it is asking a lot of them to change their editor or tools to collaborate with you. I hope you didn't mean your collaborators have to adjust to you like that.

[kps]

Not at all; the point is that a Dane isn't actually taken out of their flow to type ø in Danish, because they're using a suitable keyboard layout. Likewise a programmer need not be taken out of their flow to type (a→t ≠ 0) or a ← b ∧ ¬c or (2=0+.=T∅.|T)/T←ιN.