That 10b5-1 plans are a scam has been discussed at length on this board; note that the fourth entry in the list below was in reply to one of your posts:
I don't see how a "soft" plan could be legal. Even if the insider is leaving the actual decision of how many shares to sell to a third party, the insider cannot influence that party in any way. Here's a quote from the SEC guidance from last year:
for a Rule 10b5-1(c)(1)(i)(B)(3) defense to be available, the person is not permitted to exercise any subsequent influence over how, when, or whether a transaction occurs. The third party who has been granted discretion must not be aware of material nonpublic information when exercising that discretion.
The other interesting issue is the legality of canceling a 10b5 plan while in the possession of inside information. This currently seems to be a gray area. Here's an academic paper on this issue:
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