Thanks FST for the link! Basically, they think that one should not care about performance that much, instead make the thing sturdy:
Operations and Overall Affordability: Propulsion and Engines:
• De-rate the engine operation to reduce stress. Design and certify to one level, operate at less (example: engine operation at 90% of design/certification thrust). This should extend life through a direct increase in MTBF for many major components. A study by MSFC/Rocketdyne, "Rocket Engine Life Analysis", August, 1996, indicates a significant increase in engine life expectancy, from 10's to 100's of flights between overhauls, when operating engines at 90% rated capacity.
• Reduce start/stop transients for engines through either technologies (laser ignitors) or approach (increase propellant capacity and slow the startup). Any decrease in engine ramp rate correlates to reduced thermal shock loading on materials and increased life.
• Eliminate hypergols. Use fluids already common to the main propulsion system such as LOX or LH2. Volume and hence weight has previously limited use of LH2 in favor of toxic fluids.
• Make propellant tanks more robust (through increased weight or stronger materials with higher design factors of safety or both). This should simplify checkout and loading procedures by eliminating complexities associated with fragile tankage.
• Make umbilical interfaces more robust on the vehicle to enable automated connection and disconnection of umbilicals with simple checkouts. Fragile, flight- weight structures on the vehicle side severely constrain (or eliminate) options for automation of umbilical connections at multiple interfaces Automation would move connection time towards minutes rather than days.
• Place LOX tanks aft. This simplifies facilities for loading as well as loading procedures by eliminating failure modes and additional complex systems. If using engine gimballing, this may mean increased control authority. This in turn may involve engines placed farther apart.
• Swing arms should be eliminated or vent lines placed fully on-board. The simplification of interfaces could be improved by eliminating vent arms for cryogenic boil-off. Overboard venting may involve more robust thermal protection systems and structure capable of resisting ice formation and possible impact. Fully on-board vent lines, as another option, can be routed down and integrated with ground umbilicals to reduce overall complexity.
• Add propellant capacity to allow extended loiter [airbreathers] and eliminate non- return-to-launch-site abort modes. This eliminates costly stand-by-contingency infrastructure.
Vehicle and Structure: • Increase robustness to eliminate regular intrusive checkout and inspection. This
should be targeted on an increased tolerance to corrosion and stress.
• Thermal protection systems should increase weight if required to make more robust. This enables use of a higher impact material that is damage resistant.
• Thermal protection systems should be purge-less for zero interface support requirements. This may mean an increase in foam thickness. The elimination of confined spaces and creation of a purge-less condition is a target.
• Increase landing gear robustness. Size correctly for true “walk-around check only” reusability at expected loads, speeds and operating conditions.
• Closed compartments should be eliminated. As stated several times in the body of the report, the negative impact on operations in terms of time and resources that result from confined spaces in the vehicle cannot be overstated.
Health Monitoring and Control:
• Integrated Vehicle Health Management should increase the number of sensors focused on maintainability (ease and speed of troubleshooting, fault detection and isolation, and checkout). This should permeate fluid, electrical, and structural systems - not just black boxes.
• Electrical onboard power should provide simple, single connection and on-board conversion for simplified interface to ground during processing (airplane like). On- board ability to power specific systems as required should be built in.
Supportability:
• Increase accessibility by means of aircraft-like access panels. This includes motorized, hinged, latched, pull out access trays and operator access via push button. Maintainability, post troubleshooting, is increased, reducing mean time to repair.
• Design for self-ferry. Simplified infrastructure via the on-board accommodation of most, if not all functions required for take-off is a target.
• Use commercial-off the shelf (COTS) hardware with little or no modifications to get flight weight, i.e., aircraft weight.
Payload:
• Create more independence for the payload to simplify integration. A containerized system with a very simple, robust loading operation (sea-land type, self-sustaining containers) is a target.
I think a large proportion of newspace people have been saying things like this for a while, but it's nice to read such detailed descriptions from these NASA guys from the various centers... from 1998. 
