[EM] Anyone got a good analysis on limitations of approval and range voting?

[Matthew Welland]

It seems to me that approval and range voting eliminate most of the 
strategic opportunity in single winner elections and the marginal 
improvement of other methods is fairly small. Can anyone point me to 
analysis, preferably at a layman level, that contradicts or supports this 
assertion?

Or, in succinct terms, what are the strategic flaws in approval or range 
voting? 

Thanks,

Matt
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