That's not really the case - the A-5's internal bay could handle a
single Mk 27, B28, or B43 bomb, with all manner of problems that
go along with blowing off a piece of your airplane and blsating part
of its fuel system out of the back.
This is true, but after the straight A-5 was gone nobody really
considered it a viable way to deliver a weapon (at least that was true
by 1969)....And more than once an Vigi puked out those tanks on a cat
shot. Talk about some excitement for all involved!

By the mid '60s, though, the Powers That Be had realized that the RA-5

wa much more useful as a sensor platform. It could go places nobody
else could, and get data that nobody else could dig up.
True again, but it did retain a secondary nuke delivery role into the
'70s. Its capabilities were sorely missed in Lebanon just a couple of
years after its retirement.