Clear conclusions from the Brecon by-election.
The Liberal Democrats won because of an electoral pact. If they hadn't had one they would have lost.
The Conservatives lost because they didn't have an electoral pact - their vote plus the Brexit Party was a majority.
The Labour Party is in a deep hole.
A General Election is going to be very closely balanced and (on this evidence) unlikely to yield a clear result because Conservative gains are likely to be balanced by losses (to the SNP and Lib Dems).
The Brexit Party cannot deliver Brexit but they could stop it.