Humans prefer longwordsstucktogether.com, but you are asking alot of search engines.   They may well interpret
   freemonthypnotherapist
as
   Free mont the rapist
or
   Free month not her pis
whereas
   fremont-hypnotherapist is hard to misinterpret.

The more you ask the search engines to figure out the more likely you are to be disappointed. KISS the engines -- Keep It Simple -- for the search engines.

Underbars are not as good as hyphens.  It is official that google considers underbars to be word glue, not word separators.