The pair went toe-to-toe in the blue riband last term but the Paul Nicholls-trained Silviniaco Conti crashed out three fences from home when seemingly primed to challenge.
He tasted defeat on his return at Haydock this year but following his King George triumph at Christmas, Henderson expects him to be the main rival to Bobs Worth.
Henderson said: “Bobs Worth was the best horse last year. Silviniaco Conti did fall when you would have to say he would have been first or second. He’s (Silviniaco Conti) been in great form this year, so he would almost certainly be the horse I’d be the most frightened of and I think the one plus we do have is that the Cheltenham hill plays to Bobs strengths.”
Bobs Worth was initially disappointing on his seasonal bow at Haydock but roared back to form with victory in the Lexus Chase at Leopardstown over Christmas.
He will have a fresh adversary in Irish Hennessy winner Last Instalment this time and jockey Barry Geraghty is wary of the threat he poses.
“I was fairly confident we’d see more of Bobs Worth’s old self at Leopardstown and he was good,” said Geraghty.
“He seems well at home, he’s worked great and I’d be fairly hopeful.
“He (Last Instalment) has obviously been held up with injury, but I love the horse and I’d be very fearful of him.
“He jumps, he travels, and he’s a big, strong horse.
“He’s a Denman/Kicking King-type model — he’s a big beast.”
Cork native Noel Fehily gets the leg up on Silviniaco Conti and he has plenty of respect for both Bobs Worth and Last Instalment.
“The King George was a great race with no hiding place,” Fehily said.
“I wouldn’t have a problem about the hill. He’s very balanced, he’s not over big so going up and down hills shouldn’t be a problem.
“Last year he just got a little bit keen and for whatever reason just ran into the bottom of the fence and it just caught him out.
“He’s a sound jumper and hasn’t made a mistake in two runs this year, so I wouldn’t worry about his jumping.
“Bobs Worth is a worthy favourite, his form at Cheltenham is very good. Last Instalment just jumped a fraction to his right the last day I thought and all his form is on flat tracks.
“To win a Gold Cup is a dream, you grow up watching racing and it’s the race everyone wants to win.”
The Giant Bolster bounced back to his best wearing a hood and a visor in the Argento Chase at Cheltenham.
Having finished second and fourth in the last two renewals, trainer David Bridgwater has every reason to feel bullish about his claims.
“I think the last time he got his ground was in his novice chase at Worcester, however many years ago, but he’ll get it again at last,” said Bridgwater.
“If he jumps — and they all need to jump — and if he has luck in running — and they all need luck in running — then on pure ability along he has to be in the first three.
“Nobody else has course form this season under their belt like he has and if he has lucky in running I seriously can not see him finishing out of the frame.
“Tom Scudamore knows him so well, he just runs so much better for him, and he’s absolutely bouncing.”