Tom,
The CC of Rochester, NY completed a bunker renovation/restoration by Gil Hanse last year. CCof R is a Ross course and they used one of Ross's looks, the "grass faced" slope down to a flattish bottom. The sod/grass variety used on the slopes leading out of the bunkers and toward the L.O.P. was a 70/30 blend of fescue/blue. I think the correct blend is key and it sounds like the blend you noted is too high in bluegrass. No, I don't believe there are any "cutting edge" (ha, ha) technologies to correct the apparent problem you describe. Though I do believe there were some mistakes made with grass choices and what sounds like too much irrigation used.
I am about to begin a very similar project in September and will also build the bunkers in a similar fashion use the same 70/30 grass sod blend. Prior to my proposal to the club, also in Rochester, I met with the superintendent of CC of R, Rick Holfoth, and discussed the slopes with respect to maintenence/playability and the members acceptance...
Rick noted that during this season, they have left the grass a bit long on the slopes around 4". It also follows that the greens committee and Rick have received many complaints where the ball simply sticks in the slope and it is very difficult for the members, older and some younger, to access the slopes let alone play the shot from that position.
In this case, it seems there is no concern as to how to care for the grass slopes, they have plenty of flymows and lots of labor, but rather how long to maintain the grass. The committee and Rick would love to keep the grass longer, but as Rick noted, the pressure is building and it is quite likely that it will be cut down to 2 and 1/2 " as the season progresses. Of note, the bunker faces had perimeter irrigation installed around them to keep the grass "nice & green" and clearly this has led to much of the frustration. Our project will not have any new/additional irrigation on the faces as this is too costly, it seems to contradict the benefit of using the high fescue blend and it should help to keep the grass thinner. The super and the committee at our project will cut the grass at 2"+ with fly mows etc.