I should have looked up a few posts higher to the unecessary comment.It's still there.
You make a good point about the battery differences being multipled. However, more cells are readily available in the 68-72mm range, so I think it would've been better for it to work in that range instead of 65-70mm. Still a great light and not a scam, but could've been a little bit better.
The current battery length range allows for most unprotected and most (but not all) protected. Had the design allowed for the longest protected cells available then it may have ruled out most unprotected cells. So I think Convoy's choice was made carefully. Unfortunately I don't think that Convoy were aware that the newer shorter Keeppowers were not readily available at many retailers who still had old stock of the longer version.