Intuition v. Calculation

As I bumble through the Level 80 problems, soon to be Level 90, I wonder at what point tactical play rests on intution rather than calculation. I find it hard to believe that someone could calculate all the lines of these problems. Some run 10 moves deep in several branching lines. At some level, intuition has to take precendence in tactical decisions.

The most difficult problems for me are the ones where the king is pulled out into the middle of the board and then mated in the open. I need a lot of practice at this. I can rarely visualize the sequences.

82 days down, 73 to go
1121 probs down, 80 probs to go in Circle One