Anyone have experience with the process of patenting an investment strategy?

Lol the supreme court ruled against being able to patent financial products, let alone strategies.

The only "process" worth patenting might be an algo (yes, something actually written in code that automatically executes via computer after certain events, not "if I see this stock do X Y and Z then I do A"). People can execute algorithms but patenting instructions for how someone should do their job, really? I suppose it could be done, but what's stopping anyone else from writing down your genius steps and using them elsewhere? And if they did without your knowing, you'd have no way of discovering if they used that info. At least with a script you could hypothetically find if they're using your script, after you get a court order to have their hard drives searched etc..

What kind of strategy scales so poorly you can't even use it now?

See In re Bilski.

Assuming this is actually real, I'm pretty sure you'd want to look into trade secrets rather than patents. You do realize that patents (and patent applications) are published, right? How exactly do you see enforcement going? Not to mention...if you don't have the capital to execute this now, you probably don't have the capital to front a few million for a patent suit.