[yesthatjallen]

One way to counter this is to vote for your top choice and then list the worst, unelectable candidates as 2, 3, 4, 5, etc.

This will dilute the pool of second-tier candidates.

[Svartalfiar]

One way to counter this is to vote for your top choice and then list the worst, unelectable candidates as 2, 3, 4, 5, etc.
This will dilute the pool of second-tier candidates.

That doesn't work like that. Basically, if no one breaks 50%, the candidate with the least votes is eliminated, and all their voters change to second/third/etc choice. Repeat until someone breaks 50%. So all your method does is essentially remove your vote, instead of allowing you to have a second 'ok' pick,if your top one is no good.