>"Most people that learn to braze first have more problems
>with silver than people that learn to silver first."

i agree. i learned to braze and build w brass but switched to
silver content rods about 5 years in. when you go through the
learning curve w brass as your chosen filler rod, you learn
more about heat, heating cycles, capillary action, and a whole
host of other topics that will help you troubleshoot down the road.
too often, 'brazing w silver' has this cache attached to it as though
you can do no wrong by dint of the lower amount of heat used. i
see that as a major problem and tangential to this thread about
canti post brazing.
it's hard 'to unring the bell', but if you're a silver content rod user,
trying turning up the oxygen, or using a bigger tip, or having some
doobage the next time your near the torch. the biggest crime you
can commit is being so careful that you assume that the rod will
do the work for you. when freddy says things like 'flow the joint'
(no pun intended...) i think it's great advice. get it hotter. work
faster. use 3 x more flux. it'll work out fine, trust me.