I think that is excellent advice and wish I had taken that approach when I pulled the handle. It would have saved me quite a lot of grief.
If you plan your departure well in advance (which you pretty much have to do in Service life) you should have built a decent financial buffer in order to fund (survive?) a "thinking" gap.
Perhaps does not apply if you have already lined up/planned for your next job and career?? (Not everybody does...I didn't).
Think it would apply whatever you doing though your individual feelings may change if you have something immediately available.
Possibly something similar to retiring when if you just stopped at whatever age and gave everything up then it could have a detrimental effect on someone.
Knew via my parents over last 25 years of people who went on to age 65 in their job, leaving on last day possible and either they or partner dead with 6 months because the life change was too much and they hadn't planned it through.