..the awful past-it "Entertainer" played by Laurence Olivier, telling "the worst unfunniest jokes in the world".

Oh Yes!
What a brilliant observation!
From IMDb


I suspected from the momet I saw Corbett trip down the stairs that Forsyth had engineered his appearance to ensure that Tess didn't get the limelight!

Is Ronnie Corbett Bruce's evil ventriloquist's doll come to life, bent on wreaking havoc on the show in a vain attempt to show Tess and Claud in a bad light?

He's clearly Forsyth's Mini Me isn't he?

I dunno why he was there really - either Bruce insisted on trying to prevent Tess having the show to herself or the Beeb thought we couldn't be trusted to watch a dance show that didn't have some pantomime 'humour' in it.
Either way, it backfired quite dramatically.

They had Corbett to fill the non-existent Brucie gap.

How old is the Chairman of the BBC Board of Governors, and does he have the phone no. of the SCD Chief Producer?

A very small gap filled by a very small talent.

Tess couldn't get the limelight if you shone a 1000 watt spotlight on her.

On the contrary, RC may be very small, but he's been in the business for years - and you don't get to stay at the top by having no talent. Even if it's as someone else's sidekick.

He was there to take the pressure off of Tess, no one knew how it was going to work out, so if she'd fluffed it he would have been able to help. He was probably there as a contingency, in case things went horribly wrong, as he's got all the experience in the world in live performance (probably why they have two presenters, in case one of them can't perform). As it turns out, it doesn't look as though he was really needed, which is a good thing, but we don't know how much moral support he provided, or how it would have been if he hadn't been there.

I don't know what so many people are complaining about, he didn't really interfere with the show, and provided suitable breaks (with suitably awful jokes to replace Bruce's) which must have taken up all of 5 mins out of the running time.

Your comment proves my point.
He hasn't stayed at the top.
What has he done in the last 20 years (apart from that rather good Sky ad with Alice Cooper)?

Ronnie Corbett's skill was telling long drawn out stories.
The show would go on to midnight if he was actually presenting it.

Given that he's now 79, it looks like he semi retired, but he's done quite a few things, as well as the ads, in the last few years, just a couple of appearances a year.

My point was he did stay at the top for decades, and you don't get to do that with no talent. The fact that he may have slowed down the number of appearances in recent years in no way invalidates that statement.

With the BBC turning to Ronnie Corbett as a stand-in, and Lionel Blair's name being touted around, it seems that the BBC are hyper-conscious of the "golden girls" sector of their audience.

Well if and when the time comes, surely that would make Aled Jones the favourite to take over, as he's an ex-contestant, proven presenter, and the over-70s all know him from Songs of Praise .

Not the name that springs to my mind immediately, though.

From the mid 60s to mid 80s he performed other people's scripts, most famously those written by Ronnie Barker.
He's also famous for that astonishing slice of comedy genius, "Sorry".

His current fame is entirely due to twenty odd year old repeats of the Two Ronnies, which show he was a talented comedy sketch actor for a while, not that he was either a decent comedian, or a good live tv presenter - even then.

There is a perfect gig for RC. He could go to Last of the Summer Wine. That's full of semi retired actors/comedians.