Hate to agree with such a...shall we say unnecessarily brusque response, but the point is valid. There's no single pattern I can think of that works only on moving but not still-water. There are however patterns that work better in one water than other, so there really is nothing wrong with lastchance's query.
For the record, have not fished Simi-Seal Leeches in rivers nor streams, but mohair leeches work just fine, so I imagine they would perform just as well.