yeah - Kholi's a **** - and maybe worse for the game long term in terms of eroding respect for the umpires (and questionably the oppo). [edit: I should say, he's a magnificent batsman - I voted for him in the 'most +EV sportsperson to watch' (or whatever it was called) thread - and not purely because he was the only cricketer.
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Smith is cheating - as per the current rules - and that in principle should be clear up-able.
However, sigh, e.g., the (USA) NBA has just been going through stuff about players with body monitoring wristbands hidden under sweat-bands. In the long run I don't see how it is technologically possible to stop players getting advice about reviewing decisions.
But, otoh, why do we want to stop them from getting advice? The idea of the review systems is that on field umpiring mistakes can be corrected. Not that we should also play some meta-game: 'which team has better player judgements about umpiring decisions'.
Give teams a time limit (the one they have now) and let them at it.