Does anyone know what the official line is on baseline heat recovery is for constant volume HVAC systems with more than 5000cfm?

ASHRAE 90.1 G3.1.2.10 Exhaust Air Energy Recovery states.....

"Individual fan systems that have both a design supply air capcity of 5000cfm (2400 l/s) or greater and have a minimum outdoor air supply of 70% or greater of the design supply air quantity shall have an energy recovery system with atleast 50% recovery effectivness. Fifty percent energy recovery effectivness shall mean a change in enthalpy of the outdoor air supply equal to 50% of the difference between outdoor air and return air at design conditions."

My understanding of this is that a constant volume fan coil system in which the AHU delivers 100% outdoor air for people fresh air purposes to the back of fancoils which recirculate space air through the fan coil cooling coils for space conditioning does not apply. The reason being is that it all comes down to the total supplied air to the space, in which case only around 10% would be outdoor fresh air from the air handling unit and the remaining 90% is recirculated sapce air.

My understanding was that heat recovery is essentially required for spaces that required larger amounts of fresh air then standard systems (more than the fresh air rate required for people) i.e. spaces where direct pollution is high or spaces where there is a risk of return air from one space contaminating another space (shooting clubs, hospitals etc). Or alternativily, spaces which have high occupancy rates and therefore the amount of fresh air required for people is significantly high relative to the overall cooling load meaning that the fresh air to supply air ratio is high (i.e. movie theatres, lecture halls, assembly spaces). Because these spaces require so much fresh air realtive to total supply air, it makes sense that they should have to design heat recovery measures but why should a a basic fan coil system?

Consider this, A VAV system and Fan coil system have the same fresh air/exhaust air rates and use the same amount of energy under peak load conditions for fresh air cooling. The only time in which there is a difference in fresh air rates is when the VAV is able to utilise free cooling which doesn't involve heat recovery anyway so it can be ignored for this comparison. Why should a VAV system be exempt from heat recovery just because the return air is reintroduced the the AHU rather than to the space directly. Most of the buildings we design in the middle east are constant volume fan coil systems because free cooling could only be utilised 14% of the year and the resulting significant increase in fan energy due to transporting return air back to the AHU and then back to the space is totally inefficient.

My concern is that 50% total energy recovery is tough to beat in the middle eastern climate due to the high latent loads (especially if the building is pressurised and therefore there is less exhaust air for heat recovery). Also, currently heat recovery is only required for fan systems greater than 5000 cfm but I am told by ASHRAE that the new 90.1 standard coming soon will use the requirements currently specified in ASHRAE 189.1 document i.e. If this is true, All fan coil systems will require 50% total energy recovery (even 3 story town houses). Seems unreasonable to me.

Any thoughts are much appreciated. cheers