They preempt it to death (Dresden Files), shuffle its schedule around constantly so it does not settle in and pick up an audience (Farscape) and on and on.
Ya know, there are these things called "program guides", they used to be made of paper, but now they can be conveniently located on your TV itself.
As for shuffling around, most Scifi programs get ordinary Live numbers, but pretty good +7 numbers because people are watching when they choose to. If thats the case, then what difference does it make WHEN they air a show, except for potential advertising revenue, which people aren't watching anyway.
All I see is a situation where people are desperate to blame anyone but themselves.
They are turning into the reality show network and it is pretty bad.
Yes, it is bad, but if they can't make money from there supposed "core audience", what do you expect them to do?