As I said earlier, RadDateTimePicker (as well as RadInput and RadComboBox) should behave like an inline-block element and its behavior should be the same, no matter whether an embedded skin is used, a custom skin is used, or no skin is used at all. That is why the important display
CSS property is rendered in the control's tag as an inline style. We have decided to do it this way, rather than rely on clients to know what's this "inline-block" thing all about. Moreover, since browser support for inline-block display is inconsistent and partial, we actually render different inline styles for the different browsers. The alternative to this is to place some ugly CSS hacks in all skins and expect clients to understand and use them, which is not acceptable for us.
By the way, I was much of a CSS and web standards fanatic myself before starting to work for Telerik. Even though I still try to always adhere to standards, I have realized that sometimes rules and best practices need to be sacrificed in order to achieve certain functionality and make customers happy.
I hope you will understand our point of view now.
All the best,
the Telerik team
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