Guard disablement by path-bias detector must be disabled or removed
Currently, any three dirauths (or any two dirauths if one other one starts voting on the relevant consensus parameters) can configure Tor clients to stop using their entry guards after a very small number of failed circuit-build attempts. This is as bad for a client as having UseEntryGuards disabled entirely.
Tor 0.2.3.x users will be compromised by this without even a log message warning them that they are abandoning entry guards.
This feature must be disabled completely for now or removed. The current path-bias detector code is unsafe to use with any non-zero value of pb_disablepct
.