Not to be big brain but if you take a look at my match history you will see a plethora of allied brit games I've done - I'll let your imagination decide what big brain stuff I've been doing/testing in those recently.
For example mortar pit on Across the Rhine build in the fuel will be in smoke barrage range of axis base territory and i was able to just walk over there by chaining smoke and gib a truck in HQ sector. There is little you can do to prevent that if you don't know what cheese is coming and you only need to do one bad retreat for your truck to be sentenced to death. (Safest truck positioning in base confirmed L2P issue?) Also its not a big investment for the brit player, at worst a bit of manpower bleed and a retreat for a failed attempt. (If you have to retreat with the 2 demo team tommies just go for 5+ section build to maintain map presence
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The mortar pit needs to be up about a minute so it can fire enough smoke so that stuka counter better be damn speedy in KOing the pit in that time frame. After that the pit has served its purpose and payed for itself so it matters little if it dies.
If you were able to put up a mortar pit by the fuel in Across the Rhine, and keep it from being destroyed, then the game wasn't competitive at all. In games like that, you can do anything you want and it doesn't prove anything. One of my teammates, who plays UKF, will build 5 snipers and go big game (Puma) hunting in those games. It doesn't prove anything beyond the fact that there were too few people searching to make a good match.