The Big Blue Broken Meanie!

Today Mikey wants to talk a bit about something almost every fuser has encountered and even occasionally wonders about- the dreaded !@#$% cracked piece. 
Now, cracked kiln fired pieces are often the result of heating too quickly, cooling too quickly and/or a problematic uneven heating kiln (remember to close up those peepholes when above 500F). 
If you think it through logically, it's easy to determine when the glass broke. A smooth edge means it did so on the way up in temperature so therefore that edge got fire polished. Should the break be sharp, it has happened on the way down. 
One of the most fun and dramatic fused pieces we've done was The Blue Meanie from The Beatles Yellow Submarine (actually one of several characters from that animated classic that we've tackled). This one unfortunately cracked right in two on a third firing. 
Sitting on it for a few months, all forlorn and forgotten in the deep bowels of The Ivory Tower (Mikey's office), Mikey yanked it out the other day, laid it out on top of a yellow sheet and thought to re-fuse it back into one. 
Now, the problem with this piece in particular is that fire polished edge. This means that we are unable to fit the crack tight together and the gap will fill and fuse together but the 'memory' of that crack will always remain (see here for more).
So, to conclude, yes we can fuse broken pieces back together again so long as we place them on a base glass. Will the crack still be visible?
What do you think?...