I found Kizzy does need you to wait with her outside- but she never had an accident with me- but i was religous about letting her out as I was still trying to access her level of house training!
She works like clockwork straight after food and loves the praise after she has done her business!! I used the same technique as Muireann- just waited and waited and refused to go in as i knew she needed to go but was distracted and wanted to play with me, or chase the neighbours cat off the wall!! 
Fingers crossed she will ‘get it’ soon but some evenings she would potter around for 10 mins before she would do what she needed to do!!