...just to clarify a bunch of things:
1. I doubt strongly that there's anything wrong with the Hassy. I've had it CLA'd along with the backs, fully adjusted and lubed. I've shot plenty of jaw-dropping shots (in my opinion) with it, so it's not giving soft images or out-of-focus images.
2. I doubt contrast is an issue as I've adjusted both the Hassy and the Pentax negs to have the same contrast as an end result.
3. I have looked at prints as well from both at 16x20 with no significant difference either (although it is hard to compare when the photo subjects, lighting, etc. are all different).
4. I understand that the glass is different and that's what produces the sharp images (along with the film, aperature, shutter speed, etc.) only until you take into consideration the vibration of the shutter in question and the focusing on the different systems (which I actually find my Hassy to focus easier by the way).
The main reason I started this thread, I suppose (aside from opening up a can of worms), was to dwell on the experience of other shooters who have used similar systems and found that the margin of difference to be minimal. But I guess that's old news for most here and a topic that has been explored extensively and perhaps even exhausted. I'm still young and haven't had nearly the shooting experience of most on this forum, so I'm drawing out experience of the more veteran shooters. I've shot with 5 medium format systems including Bronica, Mamiya, Hasselblad and Pentax and it seems to me that the techniques acquired through learning how to use each system is about as important as the MFGTH charts or whatever the science behind it each system. In fact, I still go back to my Bronica 16x16 photos and compare them to my Hasselblad 16x16 photos and am still blown away that both are so close in comparison (I have 2 Bronica prints that are better than anything my Hassy has produced and sit in the "best of the best" portfolio).
I've chosen Hasselblad because of it's ease to use and the style of photographs it forces me to produce (sqaure image, angle from the WLF, etc.), the services available to it, it's durability and consistantly amazing prints and negatives (for some reason the Bronica was a hit or miss with me). The Pentax with it's 6x7 format and eye-level style is great for quicker, more documentary style photos and helps me capture moments the Hassy would be too slow in accomplishing. So, together they are an amazing pair.
Aside from all the valid points put forward by everyone here in terms of factoring sharpness, there is a kind of consistency here that I think is being ignored. I scanned close to 300 negatives and about 100 from the Hassey and 100 from the Pentax. And as much as it may be a valid point that because it's all scanning "all bets are off anyways", I have made prints with both systems as well and have a similar experience (not scientifically sound experiments though). You can throw all the charts and lines per whatever at me, but I think the experience speaks for itself and is the best measurement available 'cause I don't think the science factors in the "placebo effect" that sometimes comes with having certain brands and hype. I'm not trying to "prove" anything here -just my own thoughts and experience.