Views from the management (although not LU).
My dealings with the unions, mostly RMT, were pretty cordial. However it took the best part of 18 months to build a position of trust between us - which frankly only came about because I stuck to my guns and honoured my promises. Presumably for reasons of history trust had been hard to come by.
Generally, the reps I dealt with fell into two categories:
1) those genuine guys (and they are usually blokes) who see it as their role to improve the lot of their colleagues. Generally, these guys are pretty smart.
2) those who see it as a way of getting some easy hours on overtime (at best) or who have been in trouble, and see being a rep as making them 'untouchable' (at worst). Generally these guys aren't that smart, and have a tendency to be in it for themelves rather than their colleagues, and in some cases are forceful / aggressive to the point of bullying.
In my experience there was a 70/30 split in favour of the former, although the balance shifted the other way the higher up the union you go.
It is pretty difficult to maintain composure and not get riled in a formal meeting when someone in the second catgeory is ranting at you about something, indeed anything. Whereas it is pretty easy to resolve the same problem when it is presented in a decent manner. Without doubt, my worst experiences in any meetings (ever) have been with full time reps who were threatening, aggressive and in some cases flouting agreed standards of conduct - for example secretly recording meetings. (I would love to have known what that rep would have done if the boot was on the other foot there).
So my homily of all this is that it takes two to tango. Start by trusting the other 'side' and with time they will trust you. This applies equally to 'management' and 'staff' sides (although why we have sides is beyond me, we all work in the same company), and at whatever level of the company / union you find yourself. And if you have the opportunity to vote for a rep, vote for one who will genuinely represent you, and not the one who shouts the loudest.