In L&T, for a particular division in Mumbai, I coach small teams in delivering an effective presentation internally to their organisation's seniors. At times the coaching is to Supervisors who have to deliver a session to their newly promoted Supervisors. Recently it was for a competition. The fun of coaching such teams is that I'm working with practical application of the learning.
In training workshops, the skills are surely enhanced but chances are many of these participants may not get an opportunity to present for the next many months.
Presentation Skills / Public Speaking isn't like cycling or swimming.... once learnt, learnt for life. With these skills if you loose out on applying it regularly (at least once a week) the 'enhancement' starts coming back to the original position.
If organisations, do not provide opportunities to practice the skill on a regular basis, then the training effectivness (and thus the ROI) may suffer. Can the trainer really be blamed for this?
Or else do what this division of L&T does.... practical application.