After finally pulling more than 200 kg today I thought I'd better top and tail this thread.
Tore 205 kg from the ground today, felt so good that I jumped to 215 kg. This came an inch or two off the ground but by that point I'd knackered myself so it got no further. However, I now feel much more energised that I can grow my deadlift
Since starting the thread, I've worked through Chad's PMT plan but gained little from this. I then took a look at my weaknesses again and implemented speed deadlifts at 50-60% once per week, added good mornings as my assistance lift in 5/3/1 and have been hitting (natural) glute-ham raises hard.
Checking some of Dave Tate's videos as well I've focussed on pulling my chest up and back from the start of the lift.
So, it look me three years to find the answer, but I got there! Now on to 500 lbs...