Rod,
Your question is a valid one. No, I don't have a problem with the grip of the D.E. My hands are average size or a just a tad smaller when compared with the people at work. I should note, that I shoot with both hands so I don't find the size to be a problem. I can properly grip the pistol with one hand but, with all that weight, two hands are really appropriate for proper control.
I run into many comments along the lines of yours when people learn I carry a Glock 20 concealed. Perhaps there is some visual illusion when people just look at the pistol. When trying on the D.E. for size, I place my finger on the the trigger in a normal manner for firing and, roll the rest of my hand around to the back strap. This allows me to take the grip I need to use the pistol properly. In this manner, I catch the back strap of the pistol in the meat of my palm below my trigger finger. Yes, it is a full grip but, I have the elements I need for proper control. If the backstrap were into the web of my hand where recoil would act upon the web of my thumb, that would be unacceptable as I would taking the recoil of firing in the joint of my thumb instead of the meat of my palm. Technique can make a difference with this pistol and, I believe that is why so many people either love it or hate it. I don't find much middle ground. Now, when you add the second hand to back up the first, you have a solid shooting platform.
I will note that I normally shoot all my pistols with two hands unless practicing some special drills where I shoot one handed (both left and right). Most of the pistols I shoot are considered large to huge by most people so, perhaps I have become "conditioned" to large grips. I even put larger grips on my wheelguns when I throw the stock grips away (larger surface area to spread recoil so those hard hitters don't "bite" so hard).
Sid