I work for this company and readily admit to not knowing the details of this incident yet, but the consensus amongst the guys I work with is that it was only a matter of time before something like this happened. Whilst slightly ironic due to the position this capt holds, I'm sure it will come as no surprise that this particular captain got there first.
The company fuel policy is simple. It reflects JAR ops requirements, but asks that crews do not carry more than they require. This for some reason is misinterpreted as pressure not to carry extra. I take this to mean, If you think you need it, take it. I do and so far no one has questioned me why. If there is a chance of snow closing your destination runway I think its sensible to take extra. Assuming the details posted above are correct, IMHO its appears an error of judgement was made.
This is a regional operation, the cost fuel burnt carrying the extra fuel really is tiny compared to this sort of carry on.
For example..... on the plog there is a burn correction figure given for different aircraft weights. For a domestic sector we are talking an adjustment of around 20kgs per hour per extra ton carried! To put this in perspective, carrying an extra ton gives you nigh on an hours holding! So for 20kgs, i dont understand the problem, if you think you might need it, take it and save everyone the stress.