I saw an interesting video by vshpigel two or three years ago and started viewing others. I saw something in another video that I did not believe and decided to form my own opinions strokes. But I think a lot of criticism is often called for with internet information.
What are the current ATP players doing on the forehand? I have not studied the stats but believe that most use the circular as Dan Brown describes. I think I see different foot work when running to get body rotation. For example, when running with body momentum, plant the foot that causes the body to rotate as for a forehand or backhand.
I'd say current forehand is most often get into position and do the circular forehand. That is their preference IMO. If on the run that would be different. But I think stats would show they get in position and then do the circular motion when they can.
Djokovic is my model for the forehand. I would call him circular as Dan Brown describes in his video.
Strokes are often generally discussed in terms such as 'unit turn', 'body turn', 'rotary' or other terms that are clearly different than the 'step forward' instruction. But these new terms tend to leave out 'separation' which is essential for using the powerful stretch shorten cycle of the trunk. Unit turn can be a misleading term since separation is the reality and means that different amounts of rotation are occurring for the hips and shoulders, there's twist.
Do you have
some current ATP forehand players that step forward as opposed to moving into position and doing a circular forehand as Dan Brown shows and describes as the modern forehand.
In addition, you can see in the Dan Brown video that the 4.5 player's left knee is planted as his body is rapidly turning and it seems stressful as Brown describes. I think that Dan Brown's video is a model video of how to explain and illustrate clearly his points.
What I believe is really important for all forehands is the uppermost body turn back and then forward. This occurs the forehand is circular or linear. Also, nothing illustrates uppermost body turn in the linear and circular forehand better than Dan Brown's video at 4:30.