Some Things about Proxy List (no replies)

Usually I use FRD with a proxy list

The first:
It might be my illusion, I've found that FRD always intand to use the slowest proxy server
Is it true or false?

The second:
I totally have no idea about the mechanism how a proxy server is chosen by FRD
Would someone please explain it to me?

The third:
If minimum speed could be set up for proxy server, it would be very handy