Hmm.
I kind of agree - if there's an issue it comes down to the 'minimum of 1 range band' in a manoeuvre action.
15 hours ago, Avatar111 said:that also makes it that you CANNOT move even 1 range band in "climb mode" unless you pass a minimum Tn2 check (or use air opportunities) in skirmishes. which is also FINE
Essentially it boils down to 'you can't use your free 1 range band move' (either the default one or the one you get for selecting a manoeuvre action) to make a 'challenging move' (defined as anything 'worse' than entangling terrain).
'Impassable' must logically be a terrain quality that can exist, even if it's not in the book; for extreme examples, a mirror-smooth vertical wall, or a bottomless chasm, or whatever, which cannot logically be traversed without special provision.
If you can only move across less extreme examples of such 'terrain' with range bands of movement 'earned' by passing a check (at TN2 plus any TN increases appropriate to the terrain), not with 'freebies', then you have an interesting counterpoint to normal movement situations - Water or Fire will move faster over 'open terrain' - Water by getting a free one-range-band move and Fire by getting more successes on the check, whilst Air and Earth will move faster over 'extreme terrain' - Air by ignoring the fact it's vertical, giving you back your 'free range band' move, Earth by ignoring any TN increases on the terrain.