OK so I had my grumpy head on last time. the them and us thing was a response to the reference to a nut designing the procedures - the procedure designer usually being one of us on the ground! Less grumpy head on tonight.
The design criteria for all instrument approach procedures (including missed approaches) in in ICAO PANS-OPS (Doc 8168). I think this gives lots of options but recommends the straight ahead solution where possible. Unfortunately this document still has to work for less sophisticated locations and is often based on the lowest common denominator of a simple procedural only ATC environment and doesn't cater well for the modern European environment with high traffic density and lots of radar.
WF picked me up on the straight ahead until when? thing - if you go back to the original post MEL-able seemed to be asking for all missed approaches to go straight ahead - I was trying to point out that in a radio fail situation the procedure has to go somewhere or I guess turn back to the airport which is what Heathrow's do.
Gonzo says that I might be surprised how many aircraft just go straight ahead regardless of what the procedure says - I'm not! But I'll deal with each go-around indvidually to get it back into the sequence as quickly as possible if there are no problems.
Which leads to another question - when was the last time you flew the full missed approach (or made an aircraft follow it) except for training. In most cases you'll either be vectored back into the circuit or be given different instructions because the end of the missed approach is not normally a good place to have an aircraft (from a controllers viewpoint). But if the aircraft or ATC has gone radio fail - and it can still happen - its nice to know what the aircraft should do even if it doesn't do it immediately.
The point about why not use the paired DME I would guess is because it will be because there's a difference (in ICAO terms if not for real) between a paired DME that is only certified for use with the ILS and an en-route DME - I'd lay money that the design book says that you can't use the paired DME for a missed approach.
Sorry for the assumption you'd be able to select all the aids needed - it's certainly a point that's been made during the approach briefing on all the fam flights and flight deck rides I've been on and no-one's mentioned the problem.