The Resident Patient...WORST ACTING in the series

I love all of the episodes, from the Adventures, to Return, to the Casebook, and Memoirs, even (most) of the movies. I can throw in a disc and be entertained just by Brett...Fantastic. All of the episodes are superbly acted...excted one.
The Resident Patient. I love the beginning with Holmes and Watson in the barber shop, then walking arm in arm to through Baker Street. I especially love how the camera pans up from the front door, to the window where Mrs. Hudson opens it just as Holmes and Watson are walking in, and smiles. That camera pan takes my breath away.
But the acting of Nicholas Clay as Dr. Percy Trevelyan was wooden, stiff, and horrible. The man was worse than Hayden Christiansen as Skywalker in the Star Wars Prequel. The second worst actor in the episode, you guessed it, Patrick Newell as Blessington.
Obviously this is forgivable seeing as every single episode (from Adventures, Return, Casebook, Memoirs, and the Films) has amazing actors. I've even though before, the actors they have for bit roles are amazing. But not in this episode. It's sad to see a great story, and a great episode on the whole, have such wooden acting in it.
I almost feel bad saying this seeing as Nicholas Clay died in 2000, but I don't think he would mind. he seems like an actor who would have appreciated the critisim.
But...again, it's forgivable. Seeing Holmes crawl around Blessington's room makes up for it.
Any thoughts?