I would like some feedback on my bicycle security strategy.
Ideally when I can find a parking meter, parking sign or bike rack, I will use a high-quality disk-key type
U-lock to lock my frame the post.
But often there are times like in San Francisco, where the only available stationary object is a telephone pole or street lamp which is too wide for a u-lock. This is where I will use a cable lock.
I've thought about supplementing the cable lock, by then using my u-lock to attach my back wheel to the frame. This would require a thief to break off two different types of locks to ride away with my bike.
Is this a reasonable security strategy?

I do that if I am only locking up for a short time. A theif need not ride away on your bike to steal it.

The only way not to have a bike stolen is to have your butt or your hand on it at all times. Even that doesn't work sometimes.

I use a D Lock lock and a Hawser. Weighs a ton so dont take it on rides often. Hawser through the wheels- frame and seat rails then round an immovable object before being locked with the D Lock that also attaches the Frame to the immovable object.

But if a thief wants your bike- it is going.

Most cable locks are VERY easily broken.

The extra nuisance value of the u-lock will help, but you'd be better off using a chain. Yes, I know that they're heavy!

I won't rely on a cable lock for any given time expecially in big cities. Perhaps a Kryptonite NY chain would be better suited. Though heavier theres a higher chance your ride will still be where you left it.