Don't see how in ruins the idea of tactical voting. Even if it does turn out to be less of a Brexit election, a lot of people don't want another Tory government for many other reasons, especially one run by Bois the Lair.
I was talking about 'efficient tactical voting'. If as I suspect Farage makes an arrangement with Johnson, the leave vote will be fairly solid. The differing stances on Remain, or indeed whatever we can call Labour's position, will make this harder unless there is a clear lead from the parties themselves, I don't think that is going to happen.
To take an example, a friend of mine lives in Rees-Moggs constituency and was wondering about who to vote for to get him out - now it's problematic because last time Rees-Mogg got 54%, Labour34%, LD 8%, Green 2% - so Mogg just needs to get the same vote - but there is meant to be a Brexit candidate standing so you think on that basis all get behind Labour, except there has actually been an opinion poll done in the constituency (Which won't be the case in all constituencies) and that gives Tories 44%, so in theory beatable, Labour 14% !!!, LDs 28%, Brexit 7%, Green 3%. So if there wasn't an opinion poll, the obvious vote would have been Labour tactically but that isn't the case once you see the poll. Even when you see the poll and decide to vote LD, then is there much chance of Labour voters all going to the LDs without them actually standing down? There are many Labour voters I know who would see the LDs as just yellow Tories after the coalition and will never vote for them.
And all that's not even taking into account that a good number of Labour voters are leave.
I strongly suspect there will be no Brexit candidate in this constituency