I like this option. I have previously use a strong towel to generate the friction. I like the wood option.Myself, rather than razor blades, I use a small piece of softwood, applying pressure to break the bond. The wood is harder than the silicone, but likely softer than the tub, so less likely to cause damage. Followed by scrubbing with cleanser.
I would skip the remover like SPS-1 said. Silicone is just so inert that nothing works well on it and you will be exposing yourself to some nasty stuff.
Best stuff to use here is elbow grease.