Pamela....You have control as a player. If the play is too fast, don't be pressured into accepting the dealer's count of your hand. Do not make your hit/stand decisions before you are comfortable with what your own hand count is. If they fly too fast in counting the dealer's hand, STOP them and count them for yourself also.
Personally, I like fast play. However, if you are playing for comps, time at the table is a primary factor and in that case, slow play is what you want.
As for dealers INTENTIONALLY miscounting....sure, it's "possible" but highly unlikely. I can't imagine the trouble the casino could get into for using those tactics.