Ainda não testei, mas sua proposta é bem interessante. Basta saber se funciona de verdade 
http://developer.java.sun.com/developer/technicalArticles/Programming/GCPortal/
Segundo o site, o GC Portal “enables analysis and performance tuning of Java applications from a garbage collection (GC) perspective by mining the verbose:gc logs generated by the JVM. GC Portal is a one-stop page for GC issues and includes an extensive collection of whitepapers, case studies and other material. The Portal is intended to be used with HotSpot JVM from Sun Microsystems, distributed as part of Java 2, Standard Edition (J2SE). Use of the GC Portal enables developers to model application and JVM behaviors from a GC perspective.”
Abraços,
