I recently came across flickrer Sarah London Textiles who not only makes granny squares in totes cute colors and designs, but also provides an EXCELLENT photo tutorial on how to join your granny squares.
The way I intended to join my squares together was to lay them all out and sc them together in two-by-two clusters, then sc cluster by cluster, and continue sc-ing clusters exponentially. I'm sure it'd work out fine that way until I discovered SLT's tutorial. I'm completely new to everything crochet so I don't know if there is an official name for this particular join the way it is with knitting, but the basic idea is to simultaneously connect the squares to each other on their final rounds. What?! Yes, so it's pretty obvious that I came across her tutorial after my individual squares were already bound off. No problem though: I picked apart the sewn-in end of my working square and pulled until I got to the start of where my join was supposed to go. As always, only ONE loop to pick up--I love it. If you're someone who doesn't read directions (me), you'll find her step-by-step pictures are really clear and easy to understand.
After making so many squares, I'd feel overwhelmed at having to then sew them all together. But with SLT's method, there's no extra seaming; you are simultaneously finishing your working square and attaching it to the previous square . I think everything works up so much faster.
The methods seems to use less yarn (or I'm making my loops tighter) as I've found after pulling apart the last rounds and re-working/attaching, I now have all of these straggly ends to weave in.
Unless you encounter some 5th dimension time-shift, there is no way you can lose any of your diligently-crocheted squares. Ahem.
There really weren't any cons. It was a little fiddly at first, orienting myself with this method, but that's probably how it is for every first-timer.