What is the ruling on prolonging the duration of the final prostration in prayer?

The questioner : What is the ruling on prolonging the final prostration in prayer? I mean, some of our imams intentionally do this. The earlier prostrations are normal, but the last one, before the final tashahhud, they prolong it to give the ma'mum (those praying behind the imam) the opportunity to make du'a' (supplication)?

The Shaykh : A religious innovation.

The questioner : Is this not considered an innovation (bid'ah)?

The Shaykh : A religious innovation.

The questioner : May Allah reward you with good.

The Shaykh : And beware of that.