I don't think its that bad, although I don't use it in my cars, I have a mate with a 300kw evo who literally limiter launched it from every second set of lights for the last 2 years he has owed it, standard driveline front to back, standard box and ayc same/similar to the legnum, has never had a drama.
PERSONALLY though, better safe than sorry in my opinion
I had KSmods rom on my ecu with launch control. had it set to 4000rpm and it was building 10-12 psi. used it quite often.
I had a exedy HDCB clutch and I would just drop the clutch. never broke anything (although I had a ST-R diff with evo LSD)
but after I put my unsprung carbon tripple plate clutch in the first time I used launch control (set to 5000RPM) I snapped a rear half shaft clean in half
how much grip you have and how forgiving your clutch is are all factors to how hard launching is on your driveline.