I thought a bit more about this and I don't think it is like cloning (hard or soft). Cloning in the traditional CCP sense means that you need a blank brain adapted to the individual if wealthy, and generic (which can even go to animal biomass instead of human) if not wealthy. Then it prints the infomorph data right into it.
With those facts in mind, it is highly speculative that you can erase or replace a memory with another, much like you can not burn a CD image on a CD that is not rewrittable. Is memory rewrittable with the current Eve tech ? Perhaps. And then, memory tampering and partial downloads / injections is even more tricky since it's a lot more complicated than just copying the whole...
Which is what skillbooks do. And that makes me believe that capsuleer skillbooks are pieces of highly advanced tech that is probably a lot more complex than the infomorph transfer happening in the cloning process, which also explains the time it takes, considering that PF states that hard cloning has to instantly scan the brain and thus, damages it irreparably. Where skillbooks can't allow that, unlike hard cloning. The high technology included in cloning probably happens elsewhere, like in the genetic and bio engineering happening to sculpt the body out of cadavers.
That way I see 3 different things :
- Hard cloning (PF) : breach in the capsule, or jump cloning, using the exact same tech apparently but leads to inconsistencies like "how the hell do they extract the implants of the former body ?". The infomorph is transferred into a blank new body ready for him, fit to him with his own DNA and bioprints.
- Soft cloning (non PF) : scanning a brain without killing the patient, which probably requires a lot of time with a slow process and different technology. In any case, either the recipient new body is already implanted with the backup saved infomorph but put in coma, either the recipient body is like for hardcloning, which is blank, and ready to accept the backup infomorph that is stored in the meantime in a data state drive in the meantime. (I prefer the latter solution, which is less derpy / dangerous regarding PF) In any case, soft cloning can already be considered as death of the individual since the consciousness string is discontinuous and broken, thus another stream awakens, not strictly the same individual.
- Skillbooks (PF) : no brain scanning to inject it into another blank brain here. It's very specific data implanted into a living brain pattern through implant procedures. It is also not only data (explicit declarative memory) but also and most of all skill learning itself (implicit procedural memory). Where cloning involves copying a pattern where you don't need to understand how the pattern work, you just have to copy paste it and care about the recipient functionality, skillbook learning actually imply also understanding how the data transferred actually works, added to knowing how acting on the procedural memory itself which is probably a lot more complicated than just memory declarative data.
So yeah, i'm still a little bit uneasy about this being suddenly widespread tech used by new eden nerds to get their memory fix...