First off, Lefh is absolutely meta in 3v3 and up because of CB being the go to counter for mobile rocket arty which is already in and of itself, meta. So I don't think there is even an argument to be had on that topic.
Second off, you scared of putting an HQ OUTSIDE of your base sector?? Try your base sector getting shelled off cooldown for 20 minutes on port of hamburg or Hill 400. Nothing you can do. Good luck getting vision on a fixed howitzer when recon planes go down with a light breeze, everything is locked down with 7 MG42s and your calliope or any other artillery piece is getting sniped by a player who just clicked a button and started picking his nose.
A few things: Hamburg is my favourite 4v4 map and I end up playing on Hill 400 often as well. So I know on Hamburg that LeFH/ML-20s are out of range of the enemy base sector when parked outside the HQ sector barring some exceptional scatter. Move LeFHs further forward and then SPGs can shoot at them with minimal fear and with how tight Hamburg is, it's easier to get sight on a gun too because the distances are closer. You won't be able to protect the guns from a push. 7 MG42s? Is that meant to be an argument? Esp vs USF with so many smokes and tools to deal with MGs?
And in no realistic world does LeFH counter Calliope (3 direct hits in a very short period of time? What, they parked half a dozen LEFHs in the map unscathed? Incredible odds.)
I'm just going to leave this picture here from the last patch to answer any current and future comments aimed to me on this topic. I'm tired of addressing the LeFH CB topic. The moment you go up against a decent team in 4v4, it'll be raining call-ins and SPGs.
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Numbers are, in order: Weapon built/(Weapon)Losses/Inf dmg/Vehicle dmg/Efficiency
Went all out late-game building
just LeFHs as an exercise to see if it would be enough. Not even remotely close. Suicide dives with Valentines for sight showed up as well. So when people tell me that CB is outrageous and incredible, I challenge them to even
keep a vet I+ LeFH in 4v4 vs a good team.