the thread title is my question

Your aspersions while mildly amusing in their lack of vision, understanding and total disregard for a company that went above and beyond are missing the mark. The two games you are attempting to compare were designed with different objectives in mind. Halo was never supposed to have an editing kit or be modifiable. Gearbox supplied exactly what they were contracted for and then on their own time at their own cost developed the Free Halo CE game. Comparing Halo to a Source based game is like comparing apples to an orange box.

That question could also be interpreted as "what exactly is the function of portals in maps?", to which I would answer:
They are geometry which define clusters, and must follow rules in addition to the sealed world rules

But thats probably not what you were asking. oh, well.

Just be grateful that they did at least make Halo CE. If they didn't Halomaps.org most likely wouldn't exist. Think of Gearbox / Bungie next Thanks Giving.

I'm happy with CE as it is. Being able to create vehicles from scratch is pretty cool, even if it is cryptic. Theres alot you can do with tags, too. Just takes imagination and an understanding of the tools

Once again you are assuming that Gearbox had free reign to do whatever it took to convert the program to the PC. This is so far from the truth that it shouldn't need to be explained. Gearbox had very rigid restrictions on what they could and couldn't do with the game. They had to use Bungie's Tag system, they had to make use Bungie’s server based network model, they had to make it work over a 56K connection and they had to fit it all on a single CD for distribution. They also had a specific time frame to do it in. In order to do that they had to make compromises with your idea of perfection.

For example the server based model should have been a broadband requirement like it is on H2V then there would not have been any lag in network play. The specification of the program never included co-op play so AI don’t sync and in order to make them sync more network bandwidth would have been required but 56K was the standard at the time.

Your antagonism of Gearbox just shows how little you understand of what was accomplished. Gearbox fought with Microsoft/Bungie to make changes but they MS was the customer and the Customer calls the shots. Halo PC was a game ahead of its class when it was released on the PC and was very successful and profitable so Microsoft/Bungie couldn’t have been all wrong and Gearbox couldn’t have been so bad or it would not have been so popular. And then on their own time and at their own cost GBX released Halo CE and the editing kit specifically because they knew what could have been. After all that people like you bad mouth GBX without understanding why things are they way they are. It is unbecoming.

And UPSIDES! 8D Yay!!! I can drive around in a fractal!! Yay!!! oh, um...i wus just sayin

ROFL @ pun.