Spellmaking being cut due to technical reasons?
Dont give me that garbage!
Its more than likely for gameplay reasons.
They wanted to force something and being able to make your own would have allowed you to step around it!
That "something" was called Shouts.
Let me paint a picture for you:
If spellmaking couldn't be "put in" after the fact, then it was "out" of the original design concepts for the magic system. This is because "on-paper", player created spells would overpower anything shouts could produce... or maybe some other reasoning was used, but pushing out Spellmaking was a starting point just as Shouts was at the starting point. Then add in that Todd Howard stated that Spellmaking was too spreadsheety. I believe that dual-casting was likely the non-spreadsheety answer to combining spells to Todd. It is something that could be limited to address balance, just by the virtue that you only have two hands and one spell in each. Also, just take a look of the level of utilization the dual-casting mechanic has, it has no use beyond combining the same spell. So I'm forced to ask:
Does the level of integration dual-casting has in the game seem like something that justifies the effort of creating a dual-casting system? I don't think so. I think the payoff had to be bigger at one time to justify going down that path. To me that all jives with traditional Spellmaking being out from day one and a dual-casting based spellmaking system was supposed to be the replacement.
Take all this as the foundation of Skyrim's magic system.
-Shouts
-No traditional Spellmaking
-Dual-casting as substitute, it would be Spellmaking on the fly.
So Bethesda makes all the spells and their various effects and then when it is time to go back and address implementing dual-casting, they found that they painted themselves into a corner and realized dual-casting with different spells is impossible because the effects are incompatible. What would combining Ice Storm in your right hand and a Fireball in your left look like or even really accomplish if combined into one spell? Maybe console capabilities made situations worse on consoles, but doing it for the PC wouldn't have been a picnic either.
So now Bethesda has all this work in a magic system that is broken from the original vision of it. Maybe they really did take a second look at traditional Spellmaking... maybe not, but if the simplified dual-casting kind of spellmaking didn't work, the real thing wasn't going to be any easier.
In the end, Todd Howard [censored] it up and he [censored] it up from the very beginning by not realizing [or possibly not accepting] that the dual-casting solution to spellmaking was pretty much incompatible with Bioshock's style of effects, thereby turning the whole foundation of Skyrim's magic system they started with into a striped down broken mess.
One way or the other, Todd and Bethesda really stuck it to a lot of TES fans this time around. We deserved better than this... and we still do.