OM15: Herald not dreadful (wandering a bit, but WTH). What separated 1950s' Brit sites from, say Fokker, who thrashed Herald in the marketplace, was not skill, but focus. I visited Radlett in 1962: 3 lines in the same Listed (listing) shed had Hastings on Major Service, new-build and Autoland-retrofit Victor B.2, and Herald new build. Try to imagine yourself as Works Manager at shift change, moving bodies, tools, parts, grubby paper! Multi-tasking or what? Part-BEAC-owned Aer Lingus was F.27 Launch Customer, rejecting HP in part due to Fokker chasing harder for the business.
All 3 types had 1947 in common - when Victor was schemed and bid, Hastings was in flight trials, and (to be H.P.R.3 Herald) Miles M.73 was designed with 4xAlvis Leonides, because Dart then had no funding and ASM Mamba was hurting (to be H.P.R.1) M.60 Marathon.