... but the cross in the Celtic Cross is rife with triads that can be looked at elementally. If your cross is laid out as
.......6.......
...............
4.....1x2.....3
...............
.......5.......
then you can look at 413, 423, 615, 625, 416, 426, 613, 623, 315, 325, 514, 524, 463, 635, 354 and 546.
Depending on whether you think the current situation (1) or conflict (2) is more important (in general as a position), you could also make one of the positions the elemental base and look at the triads that don't involve the base.
For example, if you decide that 2 is the base, then you could look at 413, 615, 416, 613, 315, 514, 463, 635, 354 and 546 over the base of 2. So if 2 were Earth, 4 and 3 were Fire and 1 was Air, you'd have FAF/E. A would be weakened by the E base, but A is also strengthened by the two F cards (which are neutral to the base). But if you use traditional GD EDs, then the F/E interaction becomes friendly, so you have the two F cards strengthening E and also strengthening A, kind of playing both ends again the middle.
While I would look at the vertical lines in the cross, for some reason that I can't explain I wouldn't look at 789 or 8-9-10 in the staff elementally.
Rodney