Looking at the DME doesn't really help you.
If there are any turns in your escape procedure the DME is immediately out as a means of determining track miles.
Also when you level off to clean up, the reduced rate of climb during this segment makes working out the gradient impossible.
A twin engined aeroplane climbing at gross will climb at 145 ft/nm, or 97 ft/nm if climbing at nett.
In reality the aircraft will probably climb somewhere in between (assuming it took off at the performance limit weight)
When there is a MSA of say 4500 like in Melbourne, most people would round that off to 5000 and you then need to climb 4500 ft (in round figures)
this would take you around 30 track miles - more when you allow for the clean up.
Given most procedure designers would try and keep you within 25 miles to allow you to use the 25 nm MSA printed on the charts you have to have a turn in there somewhere.
It is a bit of a trap because at typical training weights most aeroplanes perform significantly better than the above, and people get a false sense of what the machine can do. Obviously we don't often take off at the limit weight, so we will probably do better than the above figures.
If there is any real terrain around the airport the GPWS is likely to be blaring in your ear because of the differences between the 20.7.1B requirements and the design criteria for GPWS.
Performance is an area that in my opinion is not really properly considered by most people (or companies or management)because it is as boring as bat****, yet we train for engine failures everytime we go into the sim - not doing training at the limit weights is irresponsible in my opinion - I am not saying every simex should be at max weight, but there should be some exposure.