John,

If you choose to program to the lowest common denominator, then your apps - from a db standpoint - likely perform at a level far below their potential.

Great slogan... but very unfair. You have turned the reality that many customers have existing investment in other backends into an accusation that one is programming to the lowest common denominator. No, one is simply meeting the needs of customers that will not buy Oracle licenses simply because the developer claims that would be more pure. Remember that your approach is in response to your single customer who happened to use Oracle. I'd probably end up with a single customer as well if I tried to enforce that logic ;-) If that is "lowest common denominator" by your definition, I'm happy to go with the revenue that my primitive approach delivers. ;-)

As for performing under potential: I use my motor vehicle at a level far below its potential as well. If it delivers sufficient to meet my "real life" needs, the fact that my car could go 180mph is a theoretical fancy, not a reason to urge everybody to buy the same car as me.

Regards

j.R