I should indeed have used a control pumpkin to be truly scientific. Remaining 'blind' in an experiment such would be hard as the outcome is not really affect by any kind of placebo or personal bias (It doesn't affect the pumpkin going mushy if I wanted WD-40 to work more than the varnish) Blinding and double blinding experimental and control groups in important especially when trying to eliminate personal biases especially where dealing with human subjects (i.e divining for water, medical trials etc.) but with pumpkins it's sohow seemed less pressing when really all I'm comparing is the effectiveness of two preservatives. And for that reason I really should have used a control pumpkin as the outcomes may just be statistical flukes.
I did at one stage envisioned just slicing them into two halves and treating each half with Product X, which would have been the more economic option and strictly speaking the more scientific as you could asses the preservative properties on the same pumpkin not merely two similar pumpkins. However carving them up was certainly more fun.
Today, I got a great deal of 4 large pumpkins from the local co-op and got them for half price. This is good because it means I won't have to scale down the designs so much and can make larger cuts which are more intricate. Which is good news for My Joker and Lord Voldemort designs and a few others I've got my eye on.
I'm pretty pleased with the way the varnish has turned out so far (based on these limited results - ask me again in four or five days when the mould has really had a chance to take hold...) My initial conclusion is I might try a mixture of a water:bleach spray to hydrate the pumpkins and kill off any lingering bacteria, before sealing in varnish (if it proves to be a good preservative) to keep them looking as good as the day I carved them which will mean I can get my pumpkins sorted in advance of Halloween.
But to test that theory I'd need another pumpkin to lobotomise and then yes, I'd use a control pumpkin if my budget extened to such frivilousness.