This example is wrong.
"Pick and Dip" multi-classing results in having the classes forced to either run the gauntlet for your Five Levels of Suck, or having to design around the Fierce Competitor with twenty Front-Loaded powers or abilities.
I didn't pull out the wrong argument.
Dipping is a potential hazard of any class-based RPG system, and is the result of having a class' "best" abilities being front loaded. One potential design fix for this is having such abilities be introduced at low levels and increase in potency only as the PC gains levels within the class (or one closely related to it). Another is to eliminate benefit gaps in the leveling of a given class.
Those individually or in tandem with each other and potentially even more options would have been fine.
And in all honesty, 4Ed does some of this- the benefit gaps are absent, for instance.
That doesn't change the fact, though, that a 4Ed PC cannot multiclass from level 2, cannot divide his XP equally between his multiclass choices for a balanced progression, cannot choose more than one class in which to dabble, and does not get the full benefit of the class in which he dabbles- all of which are available in 3.X.
This significantly downplays the much larger problem with multiclassing which was glaringly evident from day 1:
It works better for some classes than others.
Like, better on the order of "makes some classes drastically better" vs. "makes other classes worthless". To demonstrate this, answer one question: Where did 3.x multiclassing leave primary casters?
The XP penalty was either negligible, avoided, or dropped completely in every game I saw or played. Pruning the class list would have actually made the situation worse, because fewer classes meant fewer concepts that worked, due to the glaring inadequacy of multiclassing rules when it came to caster classes.
First, that has more to do with the inherent imbalances between classes than the multiclassing system itself.
Second, so what if spellcasters lose out on higher level spellcasting punch by multiclassing? This is not an inadequacy- they're opting for flexibility, and the 3.X system reflects the real downside of this quite vividly. Those who are equally talented in a variety of areas are quite rare indeed- even Michael Jordan couldn't play pro-level baseball.
Third, even if you aren't convinced that the 3.X system is more realistic, neither the answer nor the problem is about how high-level casters get screwed by multiclassing, its about the power discrepancy between high-level magic and the high-level abilities of other classes. Remove that discrepancy, the perceived problem evaporates.
Fourth, as you point out, the XP penalty is often avoided as a houserule- the obvious fix was fairly widely (though not universally) adopted. Codifying it in 4Ed would have been accepted without a yip.
Fifth, pruning coupled with better class design (IOW, well defined roles, less redundancy, more attention to the design consequences) would have worked just fine. Look at the PrCls that have some kind of spellcasting. Some of the early ones had seperate and limited spell lists or added singleton spells. Most of the latter ones simply improve the spellcasting ability of the PC's underlying spellcasting class- the more limited options are almost never used anymore.
Sixth, the 4Ed multiclassing system doesn't really address the problem of the 3.X primary caster. Instead it nerfs the number & potency of the abilities gained in the dabbled class. It "solves" one problem by creating a different one.
In a lot of ways, 3e multiclassing is about giving people without system mastery the freedom to suck. 4e is less flexible - you need one class per concept instead of a handful of flexible base classes that you mix & match - but it also does a better job of not letting players shoot themselves in the foot.
Personally, I don't see that as a feature- its watering down the game. I didn't depend upon the system itself to keep me from making mistakes- I grew up with other gamers helping me figure out the system, and then did the same for other novices as I got older.
I grew up with unedited WB cartoons. At some point in my adulthood, someone edited them so all of the "violence" was edited out. Instead of seeing Daffy Duck get his head blackened and his beak blasted to the backside of his head by Elmer Fudd's shotgun blast, EF would take aim, then you'd see Daffy closing his beak on his blackened head.
Similarly, I saw a lot of schools and public libraries remove controversial classic novels from their shelves.
In both cases, it was to "protect the children."
For me, 4Ed is just like those edited WB cartoons, or those libraries without classics. Or, more accurately, like a bicycle from which the training wheels can never be removed.
Design the game for adults & experienced gamers, and then let them adapt it for those who are less experienced (for whatever reason). Don't design the system for the lowest common denominator- here, the novice or inexperienced gamer.
