Just got off the motorway, first stretch of road fine, then approaching
the 1st roundabout just changing down to second, suddenly died without
warning while on overrun.
Clutched in quick, turned it over, fired up and started off agin.
Got to some slow traffic, and then every time it dropped to idle speed,
or on over-run, it would die. Worst 15 mins of my driving life, slowing
through the gears while braking, then trying to dip the clutch, and use
the handbrake (crawling speed) to keep the revs up with my other foot.

Had had some pretty heavy rain coming home, and wondered if something
had gotten wet. The wondered if the clutch was going an it was dragging,
so it was slowing the engine to a stall without gas.

The  eventually got home with a face like thunder, had a sit down and a
clam down, and went out, and tried it out of gear, still wouldn't idle.

Popped the bonnet, checked the throttle cable hadn't slipped, and that
the dash pot was still working. All good.
Checked for broken or shorting wiring. All good.
Checked the vac hoses. All good.
Then I noticed, the hose from the rocker cover to the intake manifold
was off. Popped it back on, and it idled sweetly again. Popped it off,
immediate death of the engine.

On mine it was two short braided rubber lengths, pushed into the ends of
a fatter piece of plain rubber pipe.

One of the braided ends had come out of the fatter rubber pipe.

So as a precaution I have replaced it with a length of silicon VAC hose
in a fetching shade of blue to match all the other VAC hoses. Fired it
up, never ran so sweetly.

God was I relieved.