So as thread title states, i was looking through the 'benefits' (differences, although some say there aren't any or as noticeable). As i read through the old posts i came across something.

pan f- primary film (35mm)
hp5-secondary film (35mm/120)
d76

Ilford mgiv rc/fiber
dektol 1:2.5, 1+2.5

First i want everyone to know i HAVE been using it 100ml d76 to 300ml. Which according to some of the replies in old posts, this is not enough developer to fully complete developing. what i have found is that my negatives are indeed kind of 'flat' if no filter is used. if i use a 3 filter, most of my negatives look okay, as in they look good but a quick flash of '5' does the contrast justice. Lately i've been reading les, and bobs, split grading techniques, and this is just what i need.

As i have gotten used to printing my 'flat' negatives, i like them more and more at his dilution. i find that pan f is to contrasty when d76 is used as a stock dilution, and that at 1+3 it is not (i might be wrong as things become clarified through your posts)

My questions
1. What would my negatives look like if i used 1+3 dilution with the correct (suggested) amount of developer? I believe 290ml is the least suggested amount.
2. Will correct amount of suggested minimum developer open up shadows more?, i used to find that pan f seemed to0 under/overexposed. Now, i don't think so.
2.5 What was i doing to the negative using less than recommended amount of developer? (in reference to shadows/highlights, during PRINTING/ENLARGING).

Finally thank you to all who take a moment to respond.