I think that if this algorithm/heuristics leaves a node untouched if it encounters ANYWHERE a readmore tag the automatism would be perfect IMHO.

If there's anywhere a readmore tag, the author seemingly not only knows about it, but also uses it. So no automatism.

If someone does not use Readmore tags and the automatism bites him by placing it somewhere where he doesn't want it to be - well a great learning effect to use it next time.

Bye
 PetaMem