It does sound a bit hurried, I agree, but the meaning of the whole phrase "Dio che nell'alma infondere amor volesti e speme" is actually better conveyed when there is no "цезура"/break after 'infondere'. And yes, Bergonzi (for example, here, with Cappuccilli: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Gc_klP5g0os.html) does sing it with a caesure. Either way, this is a beautiful duet. Replys beautifully sung here!
