Very interesting question. :)
I've seen one just lately, in Nagareboshi. It didn't disturb me; somehow, it was a needed pause, in order to close a chapter and open the next. I felt it was well done, and briefly executed, so that one doesn't feel the need to fill in the gaps.
On the negative side, I'd definitely put 49 days. As you know, I didn't like that drama as a whole. I never felt connected to any of the characters, so by the end I was just happy it finished. That ridiculous time jump was just the icing on the cake, for me. It made no sense and it felt so contrived I actually wanted to laugh, instead of crying. But then, I felt the same throughout the whole show, as if the author were trying hard to control the viewers feeling. A trick I truly hate.
Back on the positive side, the time jump in Scent of a Woman. Brilliant. It somehow created a bridge, or a narrative compromise between what we all feared and a cheesy, unrealistic marry-go-round ending. After watching it, I realized it worked perfectly.
Another good one was in Tatta Hitotsu No Koi. That was needed, for all the characters involved to grow up. And it was wonderful because it rekindled the anxiety of what might have happened. Very nicely executed.
Another silly and absolutely worthless one I saw in Love Keeps Going, a Taiwanese Drama which left me so flabbergasted I just wanted to fly to Taiwan and kick some derrieres. There it was, to quote your words: "stupid and injected into a show due to lack of creative writing". Very apt description.
