Thank you chipp - well thought out and well presented arguments.  Of course what I like best is your basic statement "Any good marketing/sales person worth their salt would allow for an upgrade path from Complete to Infinite" :)
As for your suggestions for why they did what they did

1. I dont care what games they are playing -their prerogative. But, they should still have a rational approach for their general policy for regular customers.  I dont have to accept their argument 'trust us we know what we're doing'. As presented publically it makes no sense and I have questions about it. (Of course they can chose to continue to ignore my questions...)
2. Licensing is a technical question I know nothing about. It is supperficially a good excuse but doesnt stand up to scrutiny. They found a way with the rest of the upgrades in the 'artist line', they can find a solution here. It's a matter of policy and they can adapt the technology to serve the policy and not the other way around. (but you sort of agreed already it isnt a strong argument.
3. This is in essence what they keep saying - 'we have different lines now'. But why is it reasonable to assume that once you are in the 'artist' line you(or your pocket) will never grow enough to want to use the 'pro' ? and how can they lose by allowing the switch?

You asked why I'm interested in the issue - well, I was trying to decide which version (if any) I would like. It was clear almost from the begining I cant justify getting inf and there are sufficient new features in complete compared to v6inf for me to want to upgrade.
However there remained 2 issues - (1) if I try complete and it turns out I was wrong and I really need the extra features, can I move to infinite (2) if complete is OK for now but my needs and my funds change in the future, can I switch then.
After direct correspondence -via tickets and several phone calls- the first issue was resolved - within a month I can 'return' complete get my money back (minus $15 restocking fee) and get inf at the regular v6inf->v7inf price.
But after the first month, their 'best offer' is to give me a $400 voucher for buying v7inf. This means I'll have to pay $500 and if you add the $100 I already paid for complete it's a total of $600.
(compared to $400 if I didnt go for complete first). I'm sorry, that isnt an 'offer', it is a deterant.
 I did try approaching them. I was very polite and fairly patient but it didnt yield any results
 (They have just repeated this 'offer' this morning).
What I want is a reasonable way to move to infinite in the future, and to ensure I'm not stuck in a side line which doesnt get developed and there is no way out of.
I'm not really that hopeful, but I'll try to try all I can. In a day or two I'll collect/summarize the opinions expressed here and present them to e-on. 
Wish me (and other customers ) luck.
Thanks for contributing everyone.

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