I have updated my delta calculations file and calculated the sum of deltas for each winning combinations, then the distribution of these sums.

The theorical minimum for sum of deltas would be 1 (with numbers 1,2,3,4,5,6) and the maximum is 49.

The actual minimum is 13 on draw #73 with numbers 1,5,7,8,11,13.

As far as the distribution for sum of delta, there are:

2.4% under 30;

5.8% between 30 and 34;

12.7% between 35 and 39;

29.2% between 40 and 44;

49.8% between 45 and 49.

The most frequent ones are:

49 (12.6%), 47 (11.3%) and 48 (9.6%).

I tend to agree with Lotto Tutor about the usefulness of delta numbers. But I thinks it is a good proof about the randomness of the numbers coming out.