It would be good if this will last but it would seem unlikely. I had considered a similar repair but also considered positioning the broken to the rest of the top with a couple dowels for support. I actually wanted to confirm the actual material the top is constructed of, we read and call it Lexan but I've never investigated that to confirm.
I had considered using Weld-On IPS-40. What is the Loctite glue used by Lee!
IPS #40 properties:
http://www.eplastics.com/Plastic/Lex...ESIVE-IPS40-PT