I hate it when this happens

I was on my way to work this morning, driving down I-40, 70 Mph, AC on,
just cruising along when the engine just quit without warning. No
coughs, no sputters, just stopped.

Got the car safely pulled off of the highway, and of course it wouldn't
restart, not a sputter. I checked the carburetor and two strong streams
of fuel squirted out when the throttle was worked. Next I checked the
spark, nice fat spark when the engine first turned, no sparks after that
(oh oh...)

At that point I called work and let them know I was going to be late,
then called a wrecker. Half hour later the Lark was being loaded on a
rollback and we were on our way back home.

First thing I did was pop the distributor cap and crank the engine, the
rotor didn't turn. The I disconnected the fuel line from the carb and
cranked the engine again, no fuel.

I'm not the worlds greatest mechanic but it seems like the timing gear
must have given up the ghost, so I know what I'm going to be doing this
weekend (in 100 deg. temps).

Couple of questions, if it is in fact the timing gear (the other thought
was a broken camshaft, but then it seems like the fuel pump would still
be working) what makes these things break like that, with no warning at
all? Of course it's 47 years old and designed for about 10 but still!
It isn't so much that it failed that bothers me, its the total lack of
any warning. IS there any warning these things give before they fail
that I just didn't notice?

I've heard of this happening with Studes but it's pretty rare isn't it?

Oh, and since I left my other water pump pulleys at Ray's I had to
borrow the one of the Lark to make the truck drivable again, and
wouldn't you know, it was a bit smaller so the belt didn't work (to
long). Well I got creative with two generator brackets and made that
work....

Jeff DeWitt