Ludicrous. Bayesian Regret results for instance show Approval Voting doing quite well even with 100% strategic voting.

http://scorevoting.net/BayRegsFig.html

There is even a theorem that, under plausible models of voter strategy, Approval Voting will tend to elect Condorcet winners (i.e. candidates who beat all rivals by a head-to-head majority).

http://scorevoting.net/AppCW.html

Clay Shentrup Co-founder, The Center for Election Science