I gather by the overall tone of GFs post that he's not really looking for a discussion on this but rather just wants to harrump someone elses system. (No worries, I do the same all the time)
I have done a decent split of blank fire and airsoft albiet with most of my blank fire stuff actually being MILES rather than the honor system.
I am sort of on the fence with this one. I do not like to mix real steel and airsoft as a general rule but I do see the value of limited blank fire use such as what you see at MSW events for one reason above all.
Gunfights are loud...
If there is an engagement 1K away from you, you'll know it when there is real firearms involved. You're likely not to hear an engagement with airsoft weapons 200m away which means that your overall situational awareness is skewed in a 100% airsoft battle.
I remember doing a One Shepherd event on a 2800 acre property acting as OPFOR to a Marine ROTC unit near Columbia. I was tasked as a scout and my partner and I were on rest rotation when I was awoken by the sound of a distant gunfight. Not only did we know there was a fight, we could also hear that contact was initiated by AKs and that the overall volume of fire and minimal response from M16s meant that the fight was going well so we might as well go back to sleep. Likewise, when we bounced small units with our FNs, the entire area knew that the scouts had sniffed something out and could begin converging on the area to bail us out.
That added a great deal of depth, I am sure that having some blank fire involved in MSW events contributes in the same way. Mechanics wise, it's hard to say how well it will work out, I think that has a great deal to do with the quality of players and whether or not they are at the event for an experience or just to "play the game". With the majority of the "milsim" players now being basically video game wankers or team! team! team! types I do not see blank fire use being a success in main stream milsim until an affordable MILES platform comes out and we can finally heave all of our airsoft weapons into the dust bin.