Irule to LB traffic based on least connections

Yes this is in place already, the real issue revolves around cached DNS responses by mega proxies. The GTM has a wide IP for each location pool and are balanced using round robin. Each pool has a DNS A record. There are 5 pools at each location and the pools are balanced using least connections. Once a mega proxy (such as AOL) caches a DNS response then everyone making a connection from AOL will go to the same pool, thus overloading the APP servers behind the web apps. What I am looking to do is basicly re-balance the connections with an iRule rather than using the default pool.