In-place conversion of NTFS? You either still believe in a god or need to google the price of harddrives these days. Honest question tho, why would anybody do in-place conversion of partitions?
That was pretty funny, and I agree a thousand times over. When I was younger (read: had shallower pockets) I was willing to spend time on these hacks to avoid the need for intermediate storage. Now that I'm wiser, crankier, and surrounded by cheap storage: I would rather just have Bezos send me a pair of drives in <24h to chuck in a sled. They can populate while I'm occupied and/or sleeping.
My time spent troubleshooting this crap when it inevitably explodes is just not worth the price of a couple of drives; and if I still manage to cock everything up at least the latter approach leaves me with one or more backup copies. If everything goes according to plan well hey the usable storage on my NAS just went up ;-). I feel bad for the people that will inevitably run this command on the only copy of their data. (Though I would hope the userland tool ships w/ plenty of warnings to the contrary.)
Buying an extra disk for just the conversion is wasteful, and then you need space to keep it stashed forever when you never use it. Not at all sustainable, I'd rather leave the hardware on the market for people who _actually_ need it.