You're misunderstanding "if possible" here. It means "if it can be done while conveying all that you need to convey, and saying all that you mean." "Cut" doesn't do that.
Re:Write like you talk
by cableshaft on Monday October 26, 2015 @12:20PM
(#10452374)
How about "Cut words out, when possible."?
Re:Write like you talk
by PantaloonFlames on Monday October 26, 2015 @11:06PM
(#10456045)
Twain would be pleased.
If it is possible to cut a word, always cut it.
If possible to cut a word, cut it.
If possible, cut.
But of course "if possible" is implied, he wouldn't be advising you to do anything impossible, so just:
Cut.