There are probably as many way to apply waza as there are people and situations. We (Tenshinkai Aikido) tend to practice both the full tenkan movement and the faster one you mentioned. Actually, we sometime even enter and blend fast so we can use their forward momemtum to apply ura and omote. We do tend to provide a slight lead/pull to facilitate the unbalancing and to give their mind a little something to think about (falling).
IMHO, the effectiveness has more to do with you, your training, and the situation than the waza.
Nidan Tenshinkai Aikido
Lucaylucay Kali JKD