Siege Engine in 19th printing

[Gryphon]

Hello!
I'm currently trying to figure out how new rules and cards work. My question is about Siege Engine:

Originally Posted by Munchkin Change Log

You can ride in the Siege Engine at the start of combat. It does not count against Big items in play. If you do use the Siege Engine, you are -1 to Run Away.

So (how I see it) Siege Engine is like Casting Couch now — at the start of the combat I must decide whether I use it. If I choose to use Siege Engine, it stops to count as Big item, so... And this is the point I don't catch. What is a purpose to have one less Big item in combat if I can't play another one (since I am in combat and can't change my gear)?
Or maybe this ruling says that it never counts as Big? So the caption "Big" was removed?

[StaticHamster]

It never counts towards your limit of Big Items.

It retains the Big status however because it benefits from being Big (not being able to be stolen by Thieves)

[Gryphon]

Oh! So it is like Steed, which carry itself? Thanks!

[MunchkinMan]

Actually, the wording on the card implies that if you're riding in the Siege Engine, it doesn't count against your Big Items, not that it never counts against your Big Items. We'll need Andrewic confirmation, however, on this one. . .

[Gryphon]

Well, currently I haven't new version of this card — all I got is change log...

[MunchkinMan]

I more than understood that, but that doesn't change the fact that StaticHamster made an incorrect statement that had to be corrected.