Judging by the way you told us that story it sounds like you made a line of maxims and at guns and cons and 3 is2s. Playing defensively as allies will never work at least not in the bigger team games. It sound like you sat there while the KT got itself up and ready to go and waited until they got jagdtiger. The way I do my 4v4s is that i always push with artillery support.
Sorry but you are wrong a little.
It was ettlebruck station. We took all 3 VPs. Axis were holding ammo on the left and point on the right. We were not sitting down and waiting. We tried to get them off from that ammo (there were 2 trucks converted to t2 and t3 or t3 and t4 depends how you count). Pak43, KT, few volks. We were using Katy but they had med truck somewhere.
The point is that they were doomed. We need time to break that line but then Jagdtiger came and with KT as spotter kilo everything. 2 is-2, I called another one and same fate.
Tight map, no space to flank and Jagdtiger shooting through every building.. Its just broken.
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Big, heavy, slow units without AI power should be counter by AT infantry but allies do not have any infantry like this.