Part of the reason it took so long is that it's full colour, no skin on show at all, so it's more time consuming than an equivalent black and grey piece that has much less actual ink coverage. Plus, a huge element of the design is a tree running up from the wrist to the shoulder and the bark has so many layers of colour and shading that it took a big chunk of time.
Saying that, I'm always amazed when I see people post huge tattoos that they say were done in just a few hours. I've been done by 3 or 4 different tattooists and seen countless work and never seen anyone work as quickly as that.
I'd love to see it, it sounds amazing
Maybe I've just had quick workers tattoo me. My last sleeve was done by Alex Reinke, afaik the only european member of the Horioshi III family, and he lines and colours really quickly. Honestly, my full colour sleeve from Alex was probably 20 hours, not a lot more.
Same said for my other sleeve, which was done by the late Jason Saga, IMO prolly the best UK japanese tattooer. He did my leg too - a great guy and very sadly missed.
The quickest i ever got tatted was by Tim Lehi of San Francisco - ive been a huge fan of his for years and I got a realtively good sized piece from him in 3 hours on a chance encounter with him. Never seen a guy line so quickly.
I guess it all depends who you sit in front of