Apparently, when it happened in a historically meaningful game more than 50 years ago, it's both charming and nostalgic. When it happens in the last decade and a half, it's subpoena-worthy:
Sign-stealing by mechanical means was outlawed by baseball in 1961. As for that episode a decade earlier, “I didn’t feel guilty about anything,” [Sal] Yvars told Prager. “I was just doing my job.”The link above is the obituary for Sal Yvars, a back-up catcher on the NY Giants team that won the pennant when Bobby Thompson hit his "shot heard 'round the world" against Ralph Branca.
When Branca delivered his fateful pitch, a high inside fastball, did Thomson know what was coming? “I gave him the sign,” Yvars told The New York Times in 2001. But Thomson told Prager that he had been concentrating so heavily that he had not looked toward Yvars.Bottom line, cheating is cheating. Unless it's on grainy black and while film and we wax philosophical about that time and the good old days. Because it wasn't yet illegal by definition (though clearly in against the spirit of the rules), it's gamesmanship. Just not for PED's.
(Thanks to Ron Rollins for the tip)