I don't. I think that proportional voting is not POSSIBLE. When a person votes for health care reform and loses, there is no health care reform. The loser gets nothing. If a hundred million voters vote for health care reform and two hundred million vote against it, a hundred million people just had their votes thrown in the toilet.
Capiche?
When you vote, you're not voting for a healthcare reform, your voting for a person who you will expect will vote on legislation in line with how they campaigned and hopefully that is in line with why you voted for them.
Example in a perfectly even vote between three candidates, where there are at least two issues to be decided:
Person 1 gets 33% of the vote, and supports issue A and B
Person 2 gets 33% of the vote, and supports issue A but not B
Person 3 gets 33% of the vote, but supports neither issue A nor B
Proportionately speaking, all three people got elected, issue A passes, issue B does not.
Lets add a fourth person, but they only get 10% of the vote, and they support issue B but not A.
Depending on how the representation is implemented, the fourth person may or may not get in, but even though issue B has two supporters now, it still wouldn't get passed because it is
apparently supported by only 40% of the voting population.
When there are dozens of issues and dozens of candidates, it gets far more complicated to explain, but it is still proportional.
Where proportionality doesn't work, and you seem to be confusing it with, is referendums.