A couple of poor examples i feel you used. The tag example had to be explicitly FAQ'd to be allowed, otherwise it's up for debate of acceptable. And nothing about deployment explicitly allows you to deploy there except the word "place" is used. But i don't believe "place" is sufficient to deploy in a position that doesn't fit. If it is acceptable to "place" a model that doesn't actually fit completely in a standing pose, then a model could be jammed in all sorts of places. Such as balanced precariously on walls.
Legal placement of a model primarily is defined as "can the base be fully supported by this surface." That's about it. I believe it was right after the N3 release that certain clarifications were made on the forums that 1) Climbing Plus deploying on a vertical surface is legitimate, and 2) that Engaging a Climbing Plus unit that then walks up a wall means you engage to them on the wall, and you're now stuck there (unless you also have Climb+). The issue being described in this thread is basically an abuse of extending that idea further, and including the ruling that silhouette touching counts as base to base contact.
Even without the abuse of silhouette trick the climbing plus part is still pretty silly and your engage should probably just revert to an idle in those odd situations.
I can see arguments for that either way, really, but the interaction between climbing plus and engage was actually stated to be indeed how it works. There's definitely something to be said for fixing a rules interaction that would place you in a state of limbo, though.
The mine doesn't activate in that case: either you can hit your target with the mine, or it doesn't activate. The other side of this is amusing though: Opponent Discover's your Camo token; you do nothing; they BS attack the same Camo token; *dice* the discover is successful; Ok, it's a mine so it's S0 and your BS Attack becomes an Idle because there's no valid target.
Don't think you can jump on a wall even if you have super-jump and climbing+, as you'd be declaring two different skills with one short order. If you jump against a wall, you fall down to the base and then you can declare climb as your second short skill to go up the wall. If you allow jumping on walls with SJ and C+, then you'd have to allow it for troops without either of those skills as well.
If you have both superjump and climbing plus (I think only Bran Do Castro has both), then you can declare Jump and Climb as short movement orders. Since move + move is a legal option, having both allows you to jump to a wall and climb in the same Order, but with no Cover against enemy ARO. In fact, if you are in marker state (Bran Do Castro has Camo), you could do that, suffering all AROs as Discover (since to grab the wall you have to declare the climb, or fall down). I should note, however, that unless you are "vaulting" over a chasm, climbing plus is more than enough.
Shikami also has SJ and C+. You can only stick to walls if you declare Climb. If Jump was your first declaration, then there's no way you could land on the middle of wall. Move + move is definitely a legal option, but there are ARO declarations in the middle. Example: Shikami jumps on a wall, an enemy troop can now see him on the wall and declares ARO shoot. So if the Shikami also declares Shoot back, he has never declared Climb but is still somehow in the middle of wall? I don't buy it.
" Super-Jump allows its user to declare other Short Movement Skills or Short Skills (Jump + BS Attack, for example) while jumping in the air. "
Ok, forgot the shikami XD Yes, in your example the Shikami would fall. Or he could risk taking a hit, and declare Climb as his second short movement skill (since both jump and climb are short orders for him) and get up the wall.
I was under impression that C+ allows you to move along walls without Climb declaration as per second paragraph. There is, of course, a different interpretation of that. Still, it possibly doesn't mean that you can cling to a wall unless you use a second short skill. Interesting catch, it seems.
If you don't declare Climb as the second half, you can fall, sure. But you were still there at that point before you fell, including for ARO purposes. If you choose to ignore the ARO coming at you and declare a Climb as the second half, instead of falling down you stick and move up. Where's the conflict here?
Can you please clarify if that still requires them to declare another movement skill while on the wall? That seems to be what the thread comes to.
I mean, right. I think the small thing we're talking about is this: On one hand, Jump is a movement skill which seems to be enough for it to be associated with C+. Ending one's movement on the wall by any means involving one should be no different from just using Move and doing the same. On the other hand, Jump has an extra clause about falling which no other movement skill has. The way it is worded though is that it only triggers upon failing to reach your landing location. I guess it comes down to the fact that a reference to General Movement Rules is the only thing to go by when it comes to what a proper landing location is and whether a wall can be one. Which doesn't help because general rules don't really cover specifics of what C+ or SJ allows you to do (only things like MOV, trajectory etc.).
The only thing specified about the landing spot is that it can't be narrower than the base. Even if it was a horizontal spot as wide or wider than the base C+ lets you climb as a part of a movement(no reference to long or short) "as if executing a normal Movement on horizontal ground" so it's got you covered there too, although you can't actually ever have cover while climbing
"When declaring the use of Climbing Plus during a Movement, " Technically you're correct, you're not declaring Climb, you're declaring the use of Climbing Plus. Oh boy... If only short skills and long skills were named short actions and long actions instead so they wouldnt' be confused with skills.
Since we're on the subject, has anyone mentioned that although Climbing Plus can be used as part of another movement skill, super-jump requires you to declare "Jump"? This makes it very awkward to incorporate jumping movement for fireteams or g: sync units that have a mixture of super-jump and non-super-jump units.