E4 doesn't need T4 though to reach out to a younger audience, but for C4 (and any of the big networks) they need such branding to highlight the fact it isn't the same old same old in the slot.
Unfortunately now though with the commissioning of Sunday Brunch it is the same old same old on C4.
since it will free to everyone very shortly and is terrestrial channel which should cover the rights.
I'm sure the 'Big 5' mentality will live on just as it does in America.
Give it time. There are babies being born today who will see Channel 4 and BBC One as no different to E4 or Rocks & Co 1. To be honest, I think there is still a 'Big 4' mentality in this country rather than 'Big 5' anyway.
As regards to Big Saturday morning shows, BBC basicaly had hit after hit after hit
The successful ones were the ones that took the SwapShop format and evolved it. Superstore, Going Live, Live and Kicking and in some respects the 8.15 from Manchester.
But several of the summer shows were rubbish, because they had complicated and convoluted back stories. Chiefly Parallel 9, closely followed by It's Wicked.
Not to mention The Saturday Show. That had a completely different format didn't it? I recall it not being popular at first but when SMTV ended viewership increased.
I don't the Saturday show was that different to L&K if you distill it down to its basic components.
SM TV was pretty close to the Going Live/L&K formula in some ways, perhaps that's why TSS struggled, itv were doing a similar but more established show.