National polls will not greatly influence my voting decision.'
Nor do I expect that my voting decision will affect the national result.

That depends where you live, JHW. In my ward, the Conservatives had a majority of 31. The Tory is an ERG member, the defeated Labour man was strongly remain. There was at least one vote on the Brexit dance where speaker had a casting vote, and cast it with the government (which Brexiteers overlook as it does not fit their tale about him.) Had a handful of people voted, or voted differently, that vote and possibly the course of Brexit itself could have changed.