Not really, if you take another quick look at Apereira's numbers which are pretty close to mine ~250mA for 15 minutes of airtime (cdi+plane) we're both only using up about 1250mAh for 75mins of airtime. I'd fully expect an 1800 Li-po to be still showing nominal voltage with 30% of its capacity remaining.

Everyone's definition of a "flight" is different. For me it's a fair chunk of the 600cc fuel tank down the YS's throat which is about 12-13 minutes of >20% throttle (I don't time the idle). At a comp and for serious practice I only put in 1/3rd tank.