ORC:
I’ve been doing Class 1 for a few months now and am getting to grips with reversing reasonably well. My continuing problem is leaving it too late once I’m well into the bay to straighten up the bend, so I have to pull forward to correct the oversteer on the trailer. I haven’t got my eye in on when it’s time to take the bend off, and because it takes time to bring the cab round straight it’s too late. Doh!
Don’t worry about this it gets easier with time, although it varies from truck to truck and trailer to trailer, some are more forgiving than others, eventually you will be picking almost the exact point to start bringing her straight or have enough room to do a little shimmy with the other lock on to correct.
Your doing well recognising that youve taken the lock off too late and nudging forward a bit, this is half the battle.
Thats said I still do this after 20+ years of driving (albeit with 10 years off in the middle), but then my moments of excellence when i get it right are done when no ones watching and when I bugger it up every sod and his dog is around.
Also feeling pressure as others are watching can distract one slightly but don’t worry there aren’t many class 1 drivers around who haven’t made a lash up of the smplest reverse, I mean i’ve done a nice bit of bay reversing (perfectly spaced between the bananas) only to realise I have ended up on the wrong bay. 
Don’t get me started on blind side reverses, i’m lucky to be in the same RDC when completed. 