Yes, if PHP is appropriate to the task at hand AND you have an existing set of PHP talent in-house then it would be hard to argue that isn't an optimal solution.

However, if PHP is not appropriate, that in-house PHP talent does not change the fact that PHP is the wrong tool.

If your in house 'talent' can't learn a new web framework without too much trouble, then it's questionable to call it talent.

I've never worked at a company that used Delphi, but I have complete confidence in my ability to use the language. If a person doesn't feel confident in their ability to pick up C, they are missing something from their toolkit.