quarter-hearted

— […]complete with a back flap featuring a few curiously damning remarks of endorsement, as solicited and acquired from those 'name' poets and writers who have no compunction about commenting in public on their fellow-artists' works (customarily reserving their more deeply quarter-hearted commendations for their friends, suspected inferiors, foreigners, fly-by-night oddities, and toilers in another field), […].