Daz, I've been in this same boat as I really liked what the Lucas product was. (technically I still do, to a sense.)
I really wanted a way to make it work with my own cost savings by mixing it or using it in some utilitarian way.
But Shannow in his first post really has hit the nail on the head, and the product has had a difficult time as a result to make it or stay in anyone's garage from this forum.
We all want you to get the most juice from the squeeze you put out. I do think it is making your bike feel better right now, but using Lucas is not the only way to get there, and there are better ways that won't also corner you into spending an arm and a leg for it. You can post or PM any of us and we can help give you a solution.
I know you didn't ask for it, but although using lucas (syn or original) helps to protect/fix against over-shearing (also quieting down the valvetrain and making the shifting feel a little smoother), you could also switch to a higher cold-temp weight--higher first number i.e. 10wXX to 15 or 20wXX--for protecting against over-shearing and higher high-temp weight--higher second number i.e. XXw40 to XXw50 or XXw60--to quiet the valvetrain down. (both of these should help with the shifting, too.)
Bottom line, I think Lucas does what it advertises, but does also shorten the life of your oil via dilution of detergents and anti-wear additives, which it doesn't advertise (which obviously no one should expect in an advertisement.)
If you gotta tinker midway through or something like that, then swap the Lucas for a straight-weight detergent-containing oil like SAE 30. Delo or Rotella or Supertech, whichever.
Hope you're still reading..