Scratch said:
I cycle in along there and always take the namby-pabmy route, probably for the same reason I don't go round the spaghetti junction island, I'm not afraid to admit those overpasses are scary, unless the traffic is gridlocked!
I think its a psychological thing after a coworker told me she used the horn on and buzzed a cyclist using the overpass. I told her I'd have smashed her wing mirror off if she tried that on me (I wouldn't really, I might manage and oi! and a dirty stare

), but I still don't chance it.
I worked at Lucas, Gt King Street for many years and a favourite 'after work' jolly was to go up Barr Beacon.
I would join the Birchfield Road at the Barton Arms, climb up and then under the Victoria Road Island. Then it would be 'full steam ahead' straight up to the Scott Arms using the overpasses and underpass under the Crown and Cushion.
I never got any abuse off motorists, even in the afternoon rush hour.
The reasons, I think, why I didn't get aggro' off motorists are,,
1/ I didn't look like a scumbag on a stolen bike toddling along.
2/ I didn't look like an 'all the gear, no idea' idiot getting in the way.
3/ I looked like a confident cyclist who knew what he was doing.
I also used Salford Circus ( spag J ) on my usual short route. The trick here is to approach the junc' standing up in a highish gear, looking around all the time; and giving a lot of hand signalling, then 'point and shoot' into the traffic.
This is where 'Raw Power' plays its part. Show the motorists you mean business and they'll give respect.
ps As soon as you wear a bright flouro coat with reflective panels, it says "I'm not confident".