Well, I'd like you to prove wrong regarding the City Class ships. They are more advanced than the Perry and Arleigh Burke class ships in the ASW department.
Negative K. They are impressive for their size though. Definitely better than the OHP's, but not the AB's. Their ASW systems consist of the following:
AN/SQS-510 Hull Mounted Sonar
Nice, but there are better HMS systems in use today, not just in the USN, but other Navies, and even better ones to be relased very soon and incorporated in the newer Arliegh Burke ships.
AN/SQR-19(V) Canadian Towed Array Sonar System
This is a version of the TA that most newer USN ships use, the Canadian version is detuned for National Security reasons.
AN/ Sonobouy Processing System
Not sure which system you are using here, but the system being installed on the newest of the Arliegh Burke Class ships is the most advanced in the world right now (not even the newer Tico class ships are being equipped with this).
This of course does not include any aviation assets(helos), where Canada is far, far behind.
This is the biggest and best ASW asset that a surface ship can weild versus a sub. An advanced ASW ship without an advanced ASW air asset is like a one-legged man in an ass-kicking contest.
And yes, I realize the twin bofors guns and the Sea Sparrow is a joke, but we're talking ASW here. They are also the bulk of our surface fleet now, so your point about us not having many of them isn't entirely accurate. We don't have many of them compared to the USN's frigate/destroyer fleet, but compared to the rest of the world and our own Navy we do. There are currently 12 Halifax class ships in the fleet, and they are probably the most automated and easy to fight ships in existence. Take a look at the crew compliment and you'll see what I mean.
I don't know about how easy they are to fight, or how much more automated it is than the Tico's or AB's, or whether that's even a good thing or not. I do know that 12 ships is barely a fleet, and I stand on my comment. You do not have enough, let alone many.
As for the excerise data, you can check that from numerous Canadian sources, as it was a much heralded accomplishment I got sick of hearing about long ago.
I heard about it too, but the datum I got was much different.
The sub in question penetrated the CBG's ASW screen during a simulated air raid, and another American SSN was also simulating an attack, and the Canadian sub probably got lucky since the defences were being overloaded.
They were, and according to what I heard...
The outer ASW screen was destroyed by a previous simulated air attack. The SSN had executed a close-range Harpoon attack, that caused some damage to the escorts and A LOT of confusion, and was being chased off by two of the three remaining ASW escorts.
The CVN had been damaged in the initial air attack, and the simulated damage limited her to 27 knots.
The carrier was then jumped by the Oberon, which was lying in wait for her, in a close range torp attack, and two fish found their mark as helo's were sounding the Oberon with their VDS in response to sonobuoy activity. S-3's were vectored in, and the Oberon was sunk trying to escape by the S-3's, after being boxed in by the helo's.
The CVN was severely damaged, but was not sunk. The Captains of the two Tico escorts maneuvered their ships into a blocking of the Carrier and were sunk by two of the Oberon's 4 fish. Their actions resultied in the saving of the Carrier.
As usual, the Nixie did not work.

Air operations aboard the CVN were severely hampered but not halted.
THANK GOD this was all simulated, and THANK GOD I am not a dipdunk Surface Warfare puke!
I have said it before and I will say it again... All surface ships are nothing but targets for well-Captained submarines. Period.
If you know of a tougher threat than a D/E sub on battaries I'd like to know about it.
I don't. All D/E's on batts are QUIET and DEADLY.
Sure they're slow, but against a CBG moving at 25+ knots, if you are positioned downrange, you need to be silent more than you need to be fast. And the one thing the Oberon is, is quiet.
True. She is. She is slow on batts though, and she can't accellerate worth a damn. Once located on active, she is toast for the fish on the S-3's and helos.
And finaly yes, I wasn't joking, our force structure is that bad.
Too bad. It's a damn shame.
-Skater