Don't forget that Northgate could change the gen process to compile straight from the VIP bootstraps and not bother with the old bootraps files at all. It would speed things up a bit and where would that leave IDE?
Yes, I know, and as it's part of the grand plan I assume they will at some point (v7 ...), despite the fact the VIP boots are poorly designed and rather unnecessary.
It doesn't change the truth of my original statement and certainly isn't a good reason for having no other development tools available.
All the "decent" tools I've ever used have not originated with ProIV (even if they did buy them at some point) so why force people to use something if they don't want to.
As long as we're talking hypotheticals: they could also do away with the bootstraps completely and tell us to code in XML. Unlikely but, again, it would be up to other developers to change their development tools.
There is no sound business reason for forcing people into the VIP model and ProIV aren't making themselves any friends, and certainly not gaining any new devotees (or too many customers, I imagine), by doing so.