I usually only do the careful blocking when I'm blocking the pieces
of a sweater that needs to be sewn up. After it's put together, and
washed after wearing, I don't do all the measuring and all that. I've
only made children's sweaters (working on my first adult sized now)
so I don't know if it makes any difference with the larger sizes. With
my dd's sweaters, I just machine wash (I use superwash wool) and
then lay flat to dry.