It's not as easy as "don't card that one". It's more the fact that it would take a stupidly long time to actually establish it one way or that other. Unless you think the ref should have made that decision instantly, you are asking them to take a decision to the video refs and fail to actually make a decision. In that situation, if you take it upstairs, you either give a penalty or you card Bale for diving.
Video tech would come in and then not actually be good enough to make a solid, indisputably correct decision either way - and people would have the same complaints they do now.
Video technology being an instant solution to everything is just so, so wrong. It's not at all, and ultimately does more harm than good.
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