Given that Poly has granted me the ability to time travel....

[KrazyHorse]

Because you'd, as a client, i) never take advice and ii) would hoarde information.

Both not good.

Precisely.

The social benefit from allowing clients to trust advisors probably outweighs the cost of slightly efficiency reducing laws preventing insider trading.

The victims of insider trading are the companies whose inside information is traded on, not market participants in general.

[Dauphin]

Considering the number of people who are actually convicted of insider trading, non-disclosure agreements and prohibition on trading shares by advisors (etc) could be argued to be equally effective as a deterrent and remediator.