As I've come to the conclusion that my luck just isn't up to pursuing a method of play based on progressing one of the evens-payoff options (the variance on recent sessions totalling a thousand or thereabouts spins was virtually all southerly), I've been kicking around another approach - largely to take advantage of the live wheel of doom at SuperCasino.com.
I came up with the attached. At this site, chip mins are £0.25, although there's a minimum bet of four chips each spin. I've come up with dropping a single chip on:
Line - 13,14,15,16,17,18
These cover thirty five of thirty seven numbers and provides return probs as:
Win prob of 10/37
Neutral result 11/37
Partial loss (2 of 4 units) 14/37
Complete loss 2/37
I've proved the overall returns to the House Edge of -2.7%.
If, unlike me, your luck's in and the variance fairy is being generous, it would be possible to apply some progression points to use this as a basis of a positive progression; ie when 8 units up, double the stake to 4 x 2 thereby playing with the house's money, and if 16 up double up again.
I've attached an Excel spreadsheet if anyone's interested in kicking the idea around or modifying it in someway. Removing the word "Line" in cell N6 will automatically re-cast all of the numbers to reflect the line bet being removed from the staking schedule - so only betting 3 units a spin (although at Supercasino you'd have to increase the unit value to at least £0.50 per unit to meet their minimum staking requirements). Dropping the results of each spin into column A of the "collated sessions" sheet will provide a record of results, profit/loss and a breakdown of what's won or lost what - I've dropped in some example results to drive some summary data.
Despite all of this, my luck still sucks.