Yes,I agree¡.With his glances,Jack managed to attract Ennis attention, and he got it; with his glances,he managed to make Ennis be interested in him in another way than a mere friendship; with his glances,he begun a task of seduction towards his friends; and with his glances he spoke volumes about his feelings and his fears during all these years by Ennis side.The look in his eyes was a good "weapon" to get and maintain what he wanted,and he was persistent in it both in glances and in intentions,indeed.