Right, but can you ADD a query string (actually add a program name as the URI and a query string)?
It appears so (intended or not); /var/log/ltm shows (as an example):
Mar 7 14:15:44 local/tmm2 info tmm2[5430]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar: Found Rule, Client Host=10.0.0.251, Client Path=/aaffoobar, Server Host=10.0.0.251, Server Path=/test/bbb?var1
Mar 7 14:15:44 local/tmm2 info tmm2[5430]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar: Redirecting to http://10.0.0.251/aaffoobar/
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : ProxyPasstest2: 10.0.4.184:57308 -> 10.0.0.251:80
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar/: Found Rule, Client Host=10.0.0.251, Client Path=/aaffoobar, Server Host=10.0.0.251, Server Path=/test/bbb?var1
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar/: Using default pool APP-pool
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar/: New Host=10.0.0.251, New Path=/test/bbb?var1/
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar/: 200 response from APP-pool 10.0.0.63 80
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar/: Checking Location=, $protocol=
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar/: Checking Content-Location=, $protocol=
Mar 7 14:15:44 local/tmm info tmm[5428]: Rule proxypass : VS=ProxyPasstest2, Host=10.0.0.251, URI=/aaffoobar/: Checking URI=, $protocol=