I would've liked to see a rule change to keep teams from putting an infielder in medium/shallow right field. Otherwise, I'd allow shifts. Things are cyclical and my thinking has been that it was just a matter of time before some team finds itself with a bunch of guys who make a lot of contact, have bunting skills, and speed, and has great success... that some other team copies... and so forth... and then shifts don't ever go away (I remember the Reds shifting on Boog Powell in the 1970 WS*), but they aren't used to such extremes as they are now...
*Watched on MLB Network or YouTube. I did not see it live; I was 6 at the time 
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