This is about glasshouses and stones. if you don't have the stones don't live in the glasshouses.

I'd have to go look it up to find out. On the basis that British Patents cannot be applied for algorithms (because they are discovered and not novel), I'd be surprised. But then I can always be wrong.

The blit application was written, if my memory serves, as the description of a device using a mechanically described process.

As for enforceablity I'd be interested to hear of a single software only or algorithmic patent being upheld within the UK as valid. Paying over royalties on the basis of patents is sometimes just blackmail and the suffering companies payup only because the legal expenses and subsequent costs outweigh paying the blackmailer.

The RDF claim will fail because there are too many 'men of straw' also using RDF that it would simply be too expensive for the claimant to go after. I imagine I'd be one of them as I have used and use RDF on occasion.