But this is a metaphor. You can't reason sensibly from a metaphor unless the parallels are extremely close.

If you rip the band-aid off slowly, with security cordons between Rafah and Khan Younis (or between those areas and Gaza City), then you can prevent most of Hamas' weapons from escaping, you can catch as many Hamas members as you ever could have, and you can destroy the combat infrastructure in Rafah. It might take months to set up humanitarian supplies, get everyone through security, and so on, but the outcome will be superior in terms of destruction of Hamas and the number of civilian casualties will be drastically reduced.

So I don't see that the parallel is helpful here. It's not a choice between ripping a band-aid off quickly or slowly; it's like the difference between ripping a band-aid off quickly or carefully soaking the edges with a Q-tip (since we're using brand names here) until it becomes easy to remove.

You rip off a band-aid because you're impatient, not because there's no way to do it less painfully.