In the past, they would do about 24 shows in 30 days (5-6/week). So they are definitely trying to space shows with more vocal rest in mind. I am not sure it will do the trick though - it is still a too busy schedule for high-level singing). It seems they can't (or don't want to) adopt a more relaxed schedule (like some bigger bands do, say, Iron Maiden, with a day off between any two shows).
There are so many influences on a performance, especially for a vocalist. We'll just have to wait and experience it. Night to night will be different I guess. I hope James saves some energy for the last show, in Amsterdam. Can go two ways. A last show can mean he will give a little bit extra because there's much rest ahead. He could also be worn out by the travelling and singing. The setlist(s) will also play a big part in this. Let's see what they'll bring. I'm excited.
And I probably won't be sitting out on tours from now on, because if we are lucky there's only a handful of tours we can witness. They can't perform forever, certainly not this type of music. I want to celebrate what they have done and what's still left in the can.