When is a film editor more than a film editor? When he has to save a seemingly disastrous film after it's been shot--through the liberal, creative use of music, imaginative reconstruction, wholesale removals and substitutions, inspired cutting, even the elaborate addition of footage from the film library. That's what Rosenblum apparently did with ""unpleasant"" William Friedkin's Night They Raided Minsky's, with A Thousand Clowns (in close, bizarre collaboration with film-novice Herb Gardner), with Woody Allen's Take the Money and Run--and the chapters about these reworkings provide the most eye-opening moments in Rosenblum's episodic memoir of his career as a 1940s documentary assistant-editor (working on Flaherty's Louisiana Story), a 1950s TV editor (the stupefying formula dullness of ""The Guy Lombardo Show""), and then a film editor who became known as ""an important contributor to the films I cut."" (""I've stopped looking at scripts,"" says Rosenblum, ""and have assumed the right to follow the raw material into the stronger or more appropriate story patterns it often suggests."") The most widely-read moments here, however, will be those that came with the making of The Producers, which Rosenblum edited (""crudely""--the only way possible); Mel Brooks' manic un-professionalism has been written about before, but never with such effective vitriol. Yet even with totally professional Woody Allen--whom Rosenblum admires enormously and worked for exclusively over a period of years--the creative fellow inside this editor got itchy; and he has since gone on to direct a bit himself. Surely likable Mr. Rosenblum's is far from a typical editor's story; and his more conventional experiences (as well as his chapters on the basic principles of montage, etc.) are just the stuff of introductory film courses. But filmgoers with curiosity about how some smooth-looking films really got that way, or about what got cut out and why (a probable Academy Award-winning cameo chopped for Goodbye, Columbus, for example), will find this as tempting as popcorn--and just about as essential.