ネット上のある質問者による “if and when”という表現の疑問点について、２回にわたり紹介致しました。この質問のポイントは、(1) “if and when”の “and when”部分は不要、(2)どうしても “and when”部分が必要というのならば、 “if or when”との表現にするべきだ、というものです。この指摘に対して１２個のコメントが付いています。その内、“if and when”に直接関係のある７個コメント（他の５個は、質問文中のある文法についての議論でした）を翻訳しました。
(1) By Rey on December 24, 2005 8:20 AM
I hear it mostly during political rhetoric. They don’t want to appear weak on a position but they don’t want to make such a sure statement that might bite them later. So it’s almost like a positive if statement. Sort of like saying “this is an if because no one knows for sure...but it will happen because I warned you--but if it doesn’t, we got by lucky.”
Seems to me that what would be more appropriate, given the post and the comments is a simple “If...then” construct. This allows for the uncertainty (the “if”) part, and also denotes the fact that the action (or whatever would be stated with regard to the event that might happen) would follow the actual event.
In other words, instead of “If and when the computer breaks, we’ll buy a new one”, one can simply say, “If the computer breaks, we’ll buy a new one.” Doesn’t that simplify it and make it more grammatically understandable?
I know this thread is years old, but I am behind you 100%, Jeremy (not 110%, of course). “If and when” is one of the stupidest language constructs I’ve ever heard -- and every time I DO hear it, I want to scream. The “justifications” and “explanations” you got here are useless, erroneous, sad and semantically ignorant. Hold your head high, knowing that you are right and most of these people are wrong. No matter how you try to justify it, “if and when” is illogical and paradoxical. Stop saying it!