Is the whole plan -> execution -> review loop worth it, or does the review do most of the work?

My journal started as just entries and exits and it told me nothing - the

trade was already over by the time I wrote it down. Now I write the plan

before I'm in, then what actually happened, then what I'd change. It's a lot

more work.

For those of you who've kept a journal for years: is the whole loop worth it,

or does the review at the end do most of it on its own?