Buyers remorse, then. The larger screen really does improve the browsing experience, fact, whether or not you feel bad for settling for second best.
You can fit more on the screen at a given text size so don't talk balls.
Zoom out on a normal Desire to the point that you cannot read the text as it's too small.
Now repeat this exercise with a DHD and tell me whether or not there is more information on the screen...
I honestly can't believe I'm having this discussion. Or do you believe that a screen 2" by 1" will be just as good as long as it's at the same resolution

?
Bad eyesight then...
On a normal touchscreen phone (ie one 3.5" and above) with a resolution of 800x480 then to get the writing too small to read would mean each letter would look terrible due to lack of pixel count per letter, unless you have reasonably poor eyesight.
No matter how you argue it there is no more or less information on a 3.7, 4 or 4.3 inch screen of the same resolution, heck , even a mythical 2x1" screen would have the same amount of data (although by that point you would need very good eye sight to read the same small letters, which is probably one of the reasons most screens, other than iPhones, aren't below 3.7").
The only positive in a slightly larger screen (with the same resolution) is visual stuff like videos, but then there really isn't enough of a difference to pick one screen over anothr just for the extra screen estate unless everything else was the same (for example I wouldn't buy a Desire now over a DHD partly because the screen is smaller and all other things are broadly the same, well generally worse).
EDIT: Either way the screen I have at the moment is 4" in size. I wouldn't have had an issue with a 3.7" screen for my new phone (my old one was 3.7 and comparing them side by side it's very difficult to really tell the difference in screen size, same with a 4.3" screen compared to the 4" screen) or 4.3". Due to the almost exact same size I went for the best looking screen, which was SAMOLED. If the 4.3" screen had a higher resolution than 800x480 then I may have very well thought differently (the X10 resolution, which is around 860x480 is IMO a better resolution for internet browsing because of the excess space lengthways).
EDIT 2: As monitors were brought up I'll just point out that I would rather have a 20" 1920x1200 screen with IPS than a 24" 1920x1200 TN screen as well. Resolution is king, unless you go tiny (such as Sonys 13" 1920x1080 screen *squints*).
