Tech shelving - is this a good idea?

Not every post has to be about a deep philosophical technology debate. Let's take a break and look at a simpler topic. Is the setup in this image a good idea?

Obviously, this district got some shelving from a home improvement store and mounted a shelf near the teacher's desk. On that shelf, you see a desktop computer, subwoofer for classroom surround sound, a laser printer and a DVD/VCR combo. One of the primary reasons for their doing this is to avoid the custodial dismantling of classroom technology in the name of floor waxing. If you've spent much time in a school district, you realize that summer vacation means that EVERYTHING gets moved into the hallways so classroom floors can be cleaned and waxed. Some districts have quite a bit of trouble with technology finding its way back to the proper classroom and being reconnected correctly in preparation for the next year. Either the tech staff does the hooking and unhooking (and who has time for that) or, more likely, the custodian unhooks everything and the teacher hooks everything back up. This district is obviously trying to avoid breakage, support calls or other points of frustration by mounting this shelf and leaving virtually everything in place.

Another advantage is that it saves some teacher desk space. One could also argue that it might lead to less dust in the CPU since it's off the floor.

What are the problems? For one, a teacher I talked to said she hit her head "weekly" on this setup. I don't have an OSHA degree and can't speak to the legalities of this, but I suppose one could argue that it isn't safe. Since you need to access the technology, the shelf must be mounted within reach of the teacher and therefore can't be too high. Naturally, the lower shelf height puts your cranium in the crosshairs for disaster if you forget about the shelf.

All of the cables are tied off for cleanliness and efficiency, but I suppose one could also speculate that when the technology fails, equipment would be more difficult to access for repair purposes. This may be a minor thing, but it's worth noting.

I'm sure there are other pros and cons that you can point out. This district thought it was a good idea that will save them time, so I provide it as an example and as 'food for thought'.