The ability to run off the bike is an important consideration in buying a tt bike as their specific geometry opens up the hip angle.
Switching from road bike to tri bike.
The steeper angle of the the tri bike can create a much more aero position.
At the moment i am using aero bars clip ons and a seat intended for triathlons and am really enjoying the position.
A triathlon bike has a much larger seat tube angle 76 to 78 degrees than that of a road bike 72 degrees for a typical road bike.
The major differences between a triathlon bike and a road bike is the geometry of the frame more specifically the seat tube angle.
On your road bike the geometry of the frame and the angle of the seat tube will mean you are sitting too far back to comfortably reach the aero bars.
But even pros sometimes face such challenges with.
I am looking to convert my road bike trek domane 2 into a tri bike.
I understand its a lot cheaper to convert the bike rather than buying a tri bike which are.
But for many riders a standard road bike has to serve also as a training rig and be usable in events ranging from a gran fondo to a triathlon.