Scott,
I haven't broke an A string for decades now. However, when I was real young, stronger, and easily excitable, I broke a bunch. Like the time our band opened for Johnny Winter at Toad's Place in New Haven, CT and I was playing REAL hard! I was pumped! That was a B.C. Rich bass with a similar bridge saddle like the Alembic: A sharp edge to intonate correctly. This sharp edge works like a knife on the string and forces a wedge between wraps. eventually it will weaken the core as you flex the string back and forth. The tension on the string helps to degrade the string quickly too. The more aggressive playing style, the quicker you snap the core. The wrap can break too and usually will because the bridge saddle takes a bite into it. Of all the strings I broke, only one did not break the wrap. It acted like a loose spring and took twice as long to extract through the string hole on the bridge (BC Rich). If only I had the Alembic then. I would have played with a much lighter touch having the electronics to take up where I could not get with my fingers alone. I used to use Dean Markley stst strings, stst Rotos, stst Ken Smith Rock Masters, and now the Alembics. While the Alembic string is not as flexible as a true roundwound stst string, the slightly flattened wrap sounds refined and has a depth to it. They seem to last a long time too. Of course with Alembic electronics, even dead strings can singe your nose hairs off! I really believe it is mostly your technique that is breaking strings. I have seen certain aftermarket bridges (ABM, etc,) that have fat saddles front to back which cradle the string and won't allow much lateral movement. I bet that would keep your strings lasting longer. If your bass is an Alembic, see if they can make a special set of Fat saddles to try. If it's not an Alembic, sell it - it's the bass' fault! Get you an Alembic NOW! P.S. Bob is right - contact the string manufacturer and they will replace them for you. The cost of one string is far less than a customer who says I love your strings except for the funky little habit they have of breaking.
Keurosix