I can also tell you, from personal experience, that you certainly can add too much catalyst.

On one occasion I was very impatient, it was quite cold and I added lots more than called for.

The mixtures heated dramatically, then bubbled into froth and finally harden into a gooey consistency like messy foam.

It was very interesting to watch.

The final mess was (shall we say) less than useful so don't get carried away, as I did.