Here's my take:
Chapman is a great scientist who trains his guys well. He has been a leading voice in the coaching community on Altitude Training Theory as well as Threshold Training. Numerous top HS coaches (most notably Paul Vandersteen, coach of Neuqua Valley - last years Nike XC Nationals Champs) have benefited from his clinic presentations at HS Coaching Clinics.
He does a great job with the post-collegiate group. He did a great job with Haas and the Jeffersons as well as some of the "nobodies" like Chris Powers (13:59 was his pr - i believe) and Tom Burns (~8:40ish Steeple).
The problem many people had with Chapman was that there was little institutional pride. He was also not perceived to be the greatest recruiter / communicator. To be fair - it seemed that he was beginning to move things in the right direction almost 2 years ago when he recruited a great class - Hubers (4:04/8:50) from Georgia + all the top Indiana talent - Turner (4:08/1:52/9:01 - State XC Champ), Hardacre (9:02), Poore (9:06), Weatherford (4:08), and Rich (4:16/9:21).
But in the years prior to this, there was a growing concern among Indiana HS Coaches - that the general direction of the program was wrong. It seemed that Chapman's approach was to develop individuals for the long-run (an admirable approach though perhaps not for this setting) - without much of a concern for how they performed as a team representing IU in the present.
For all the individual success that IU enjoyed - there was no real "tradition" to speak of. If there was a consistent tradition - it seemed to be that the top guys got really fit and ran fast times on the track early but often failed to compete well at Big Ten's and Nationals. If you look back at the record of the Jeffersons and Haas you will find that at Nationals - they rarely lived up to their seeding going in (Jefferson's one indoor mile title the obvious exception).
Perhaps most alarming for many Hoosier HS Coaches was the alarming frequency in which IU kids dropped out of races that weren't going well. As I wrote above - it really seemed like there was no clear team identity or tradition being established at IU under Chapman.
With Helmer - the Administration obviously saw a chance to bring in a guy who had been a part of programs who had developed a great tradition (both at Georgetown and at the HS level - Oakton? someplace in VA). He came and spoke to our Indiana HS Coaches' Clinic and made it clear that his intention was to get the program to the top-tier in the Big Ten as well as nationally. BTW Helmer also has more experience overseeing an entire Track and Field Team - something they brought him in to do.
It's a shame that the last couple of races did not indicate IU's true potential. Is Helmer to blame for this? To a certain degree he, like all coaches, bears responsibility for getting his guys ready to perform on the day. It seems that the current group of guys are on board with his vision for the program. It is unfortunate that something could not be worked out to keep Kyle and Fruin in the fold.
Regarding Helmer's Training - I can only assume that hard 200s were not a huge part of IU's preparation this past August. They might have been doing some light 200s to keep the NM system working once a week or so - but Helmer's system is heavily based on Aerobic Development balanced with developing the NM system to handle it.