: Because he doesn't seem to know any other spells?
The Baron has the binding dream. Remember, Cruniac had to shake some guard out of the enchantment that bound him?
Like General Pepper and LR said above, it seems that dreams may be limited by the skill of the caster. So the Baron's use of the binding dream may be weak enough to shake off, as opposed to Myrdred's, which seems to be permanent. Likewise, the Baron may be able to raise a few ghasts, but SB can raise a whole graveyard of thrall.
: I suspect that, if that were the case, Dispersal Dreams
: would be a lot more widespread. Conventional medieval
: tactics run into serious trouble when faced by blasts
: of recurring high explosive magic.
Dispersal dreams are more widespread. Every shade has the power to use them. People like Alric too.
We don't know if shades can use the dream of unlife, however. There isn't even proof afaik that anyone besides Balor and the Fallen could use it.