You seen to be making up the history ???
Quote a few sources for your info on where all these skills survived. !!
Lets work through a few specifics then.
When the Romans left, building in stone about stopped in its tracks.
It maybe lingered on for a while, but the net result is about the same.
Where do you think all the masons who were cutting and installing stone went. ?
What happened to all the brick making skills. ? (the Romans loved their bricks too).
Name one British built building made from bricks - for the next 1000 years ??
All the specialists making mosaic tile floors ??
All the plasterers doing plastered and painted walls.
All the folks making and installing tiled roofs.
All the skills in making hypocaust heated floors and buildings
They sure didn't hang around in Britain.
There was none of that for the next 400 or 500 years. !
And even then the Normans didn't have much of that stuff,
they had cold drafty old castles.
Albeit with a few huge fireplaces in some rooms.
We could go on and on here.
Britain post-Roman era was quite a degraded agricultural society, if we can call it that,
given the mish mash of Angles Saxon Jutes and Viking raiders/'invaders'.
Who were limited to building huts in timber...
Thats not really skills and knowledge surviving, is it. ?
As soon as you see a mosaic floor, you KNOW the brits didn't do it... !
There is some debate about this, but the evidence sure is scanty....
And gets scantier as the centuries roll on post-Roman.
[imghttps://
www.romanobritain.org/1-arc/arc_images/ ... mosaic.jpg[/img]
We diverge from the The Antikythera Mechanism.
Can you imagine if this had been discovered in Britain.
It would have turned history/archaeology on its veritable head. !!
Or maybe thats a serious NO