The ride was with 3 other riders on roadbikes carrying about the same amount of luggage.
So at the least, maybe a 3-4kg difference in bike weight, the rest considering about the same.
I did find the heavier bike and tires harder on the climbs.
My friends on their lighter road bikes would often surge ahead on the start of a climb.
The relief to this was that the gearing on my setup was lower (44/42T) and I did not have to resort to any mashing at all, which all the other riders had to do.
This did mean being able to eventually catch up on the last 3/4 of a climb as they tired out.
The other good point was that the wide 42mm tires did seem to roll better down slope and especially so if the road surface was less than ideal.
There were many occasions where I was really surprised that I caught up to another rider who had appeared to be so distant or even out of sight just from the rolling.
Overall, on this rolling weight vs better rolling on rougher surfaces trade-off, I am uncertain.
Maybe a 32mm or 28mm might be the better balance.
Lower rolling weight, with some damping and conformance to poorer surface, but I will have to swap out the tires to find out for myself.
An ice cold coffee at the mid way point