superglue makes no heat
it skins immediately when touched by water
here's how I do stony frags: (or tough softies like zoos)
-I get my frags ready in a bowl of water
-get the mounting rocks/plugs whatever ready and DRY
-get box of tissues ready
-open a tube of gel
-put glue blob on rock/plug, maybe slightly larger than the frag surface you are gluing
-take frag(handle gently, you don't want to smash the flesh between your fingers and the skeleton) and dab the water off the glueing surface with a kleenex
- hold both the rock and frag and put rock and frag together trying not to let a bunch of waer run down the frag onto the glue. twist frag back and forth like 90º one time and let go when it seems stiff.
-carefully keep frag rock upright(assume it can still fall over at this point) and submerge in the bowl of water to kill the superglue and let the little slick off the glue.
-repeat for all frags - try to do them in units of "one glue tube" worth
-once all frags are glued and set and now in the bowl of water
take bowl over to tank and set all the frags back into the system
THROW THE FRAGWATER OUT
the actual length of time coral is out of the waer using this technique is 10-15 seconds. which should put very minimal further stress on the corals which are already PO'd from being fragged
Epoxy:
2-part epoxy isn't glue. there, that's the big secret.
think of it more a cement. you make it into a shape and it hardens very hard. so, you can't glue things that have stress on them, like a big frag that wants to fall over the cliff. You could support the frag so it stays where it will ultimately be, THEN epoxy the base to the rock, THEN when the epoxy is set up move the supports and now the set epoxy won't give and fall off the cliff
the kneadable stuff just needs to be kneaded well.
here's a trick: you can adjust the stiffness of the putty by getting some water into it. the more water you mix in, the thinner/softer
kneadier??? it gets.
Try taking a hard candy sized piece and kneading it with wet fingers. the epoxy will eventually absorb the water. wet your fingers again and at some point the epoxy will get easier to smoosh. NOTE: this kicks the reaction into high gear and you will feel it start to get warm. this is your 30seconds warning that it is about to set, so get it shaped or whatever you have to do pronto
if you want more worktime, don't add water and it will set up slower.
quickly rinse your hands of all the epoxy slime before going into the tank with the kneaded wad, your skimmer will thank you.
IMO, having both of these in your arsenal is where it's at.
for instance: so I make some little epoxy teepees around some gorgonian frags (basically a little corndog=stuff on a stick

)
2 days later, when the stick part erodes away a little, the gorgonian falls out of its now too big hole. expect it.
so now you have to get the teepee and the frag out, dry the hole, stick some superglue in the hole and actually now glue the frag to its epoxy. see how that works? =great. (frag back in bowl, dab frag, yada see above)
you probably could incorporate this all into one step if you want.