An actual formation landing seems unnecessary.
Possibly, until you find yourself in a situation where fuel state and deteriorating wx severely limit your options.
In fact, the maneuver itself is no more difficult, nor significantly more risky than any other fighter maneuver for an experienced fighter pilot. C course (experienced) trainees generally did their first one in a single seater, as gums pointed out, even with two-seaters available....just a routine event done last on the task list of a particular syllabus mission. The skill may not be easily mastered, but once you get it....you got it, no reason not to have it.
The question here may or may not be the required IP supervision in play here to assure that the naturally uneasy wide-eyed student gets that experience, not the difficulty of, nor the rationale for doing the maneuver. Of course, not every student is the right fit for fighter aircraft. This is UPT, the cherry....everything is new....and scary.
I've dropped wingman off underneath on snow covered runways and come back around for a 'relaxed' landing when possible. Without a doubt the preferable option....if available.
