"A below the line vote is exactly the same as a vote in the lower house"
This is incorrect and somewhat misleading as the method of distributing and counting the vote the Senate is different.
Surplus Transfer Value
The calculation of the surplus transfer value is not proportional to the value of the vote., The system that is in use was designed to facilitate a manual count and the surplus transfer value is calculated by diving the surplus value by the number of ballot papers This distorts the outcome of the election as some votes increase in value and others are reduced in value disproportionally to their original value.
This can add up to to the equivalent of 70,00 votes
Distribution of preferences from excluded candidates
Another issue is the method of redistributing votes form Excluded candidates. A vote from a minor candidate that preference a major party is often ignored and transferred to a candidate lower in the voters nominated choice of preference. The order of distribution has a significant impact on the results of the election and in Queensland 2007 elected the wrong candidate as a result of the order of preference distribution.
The guiding principle of a preferential count being that votes from an excluded candidate should be redistributed and counted as if the excluded candidate had not stood.A preferable option would be to rest and restart the count a fresh on each exclusion, thus giving expression to the voters intentions. Full value votes should always be allocated to the first available candidate that has not been excluded from the count. If I vote one for Joe Black and second preference to the LNP or ALP number lead candidate then my vote should form part of their surplus on exclusion of my first chosen candidate.
The reason this is not done is that in a manual count the time and effort to do a reiterative count would be prohibitive. However this is no longer the case as votes are now counted and redistributed electronically with the aid of computers.
Whilst the current system excludes remainders from a division there is no reason, with the use of computer technology, why the remainder value can not stay with the value of the vote.
Calculation of the "Droop" Quota
The use of the "Droop Quota" is another aspect that distorts the proportionality and accuracy of the vote. There is no overriding justification to divide the total number of votes by the number of vacancies plus one. Its a bit like dividing a cake by seven and throwing away a slice to serve six people.
The system in use is out-dated and is in need of serious review and reform