Siphon retrokits

[RustyB]

I see that my new boat (hull 318) has these siphon kits added. Can anyone please shed some light on
1. Reason Catalina supplied these kits -i.e. What problems do they address?
2. Has anyone had problems with a P-trap effect caused by a slight dip in the exhaust hose between the exhaust riser and the muffler? My mechanic says this is creating the possibility of a shorter-than-desired dead rise (should be 11" according to ABYC standards) from water level in muffler and riser...which could result in some water being sucked back into the riser as the engine stops.

Any feedback on the above would be appreciated.

Thanks,
Rusty