[1.2.328] Battlemages get their spotlight

So we can't put our 3rd Job SP into 2nd Job skills anymore?

This is not it. What Takebacker meant was, something like this;

You used the sp reset given on a 4th job character, getting hundreds of skillpoints back.
Instead of seeing a total of (example) 350 points, you now are able to differentiate, 60 for 1st job, 120 2nd job, and so forth ...

You wouldn't want to accidentally put 4th job points onto 3rd and so forth, in which some people worked their way around it by putting 4th job skills first. And another problem might happen when this is done is you don't realise you've spent all your 4th job skill points when you still wanted something else (meaning you prioritised incorrectly). It is now easier because everything is laid out crystal clearly.