Let me quote you the exact reason why you are wrong, they have not told the Pontiff where to "stick it":
Dispatch to all temples of the Conclave.
The WIT ask that the Pontiff allow the tithe of the WIT and the CJS, + all vassals of the WIT (OoC: hereafter named, we'll be certain to inform you if there are ordinary temples who are not within the WIT sphere) that our tithe be used towards the army keeping guard on the Alamien and Tuornen border to the Five Peaks, from whence the undead still strike all Anuire.
(OoC: This obviously includes a detailed rundown of the WIT forces in question, I'll send you a detailed list asap)
The WIT will pay any and all tithe that the Pontiff righteously demands, only we ask this excemption with honour and with a strong sense of the duty that our constant vigilance demands.
Prelate Kharnmoien of the WIT
Obviously this statement completely drowned in a drawn out argument over the Pontiff's threat of war against any temple that would not pay it's tithe.
I say again; your assumptions are what will draw out this conflict.
That particular quote was not drowned out - it was exactly the one which told the Pontiff where to stick it in Robbie view .
Let me translate as Robbie heard.
We are all for paying the tithe - we signed the charter so we have to.But we aren't going to. We are going to pay for the troops we would support anyway, place them where we want them to defend our interests and ours alone, and we aren't going to pay a penny to the Conclave.So Robbie sees it as: The WIT tried to strongarm the Pontiff into waiving the tithe for the WIT and every single temple under it - He said no.
They refused to negotiate a settlement of half, quarter, whatever - they refused to pay a penny. Thus the constant arguments and pain.
If they'd negotiated, explained their need, the benefits to other people, and he'd been obdurate, then the WIT might have got robbie's sympathy, but they didn't. They just demanded...
Now certainly Wallac trying to push for the war tithe in that atmosphere was going to be tough, and I expected the WIT to throw a strop, but given the long time lag between mustering and training it wasn't unsurprising - I saw it as a stalking horse motion - expected to fail but raised so that in a few seasons he could say 'see where we are, we must act this time...'
I see the real issue between WIT and IHH (and HA) as totally opposing views of what the Conclave is for.
HA saw the Knights as core to the Conclave, a single unifed force unaligned with any particular temple who could thus act with relative impunity. As such paying the tithe was absolutely necessary, simply paying for your own troops, particular in WITs manner where they were not even nominally placed at the disposal of the Conclave, was a direct attack on the entire point of the Conclave. Frankly a simple discussion group is of no interest to the Aegis and the glory of being Pontiff at best a distraction from their purpose so neither is given any importance, which pretty much leaves the knights, and maybe the ability to provide a united front to the nobility.
The WIT, I think, see the knights as at best a distraction, they are big, they are rich, they have their own large powerful army - and the knights are at best a rival - worse the knights are right next door. So they want to avoid paying the tithe at all costs as it supports the knights (bad as a nearby rival is made stronger) and reduces their own forces (also bad as they lose influence locally). To them the main point of the Conclave was presumably the discussion group - so that they could influence through diplomacy all temples across Anuire, make best use of the Pontiff role (smaller temples are less able to capitalise on advantage, with their vassals they would sweep up each time it came around to them) and so on.
Now if the Conclave had voted to change the tithe rules, agreed to maintain only a small force of KoH, etc, HA would have been fully in support of the WIT's position - but coming from the 'we have agreed to pay the tithe unless the Pontiff says otherwise' the WITs view was untenable to Robbie as it simply broke the treaty.
The interesting question is, can we agree on what the Conclave is for? What the Knights are for? Unless we can, then we can't agree the size of the tithe, or the conditions of payment...