Allergy shots

The Cochrane database recently published this review on allergy shots for rhinitis. They retrieved 1111 publications of which 51 satisfied their inclusion criteria (looking for RCTs with placebo-control) and in total there were 2871 participants (1645 active, 1226 placebo), each receiving on average 18 injections.
Duration of immunotherapy varied from three days to three years. Symptom score data from 15 trials were suitable for meta-analysis and showed an overall reduction in the immunotherapy group and medication score data from 13 trials also showed an overall reduction in the immunotherapy group.
It is good to see some good quality data on that. However, I was amazed by the number of shots. Where I was in practice patients would be on weekly or monthly shots for 3, 4, 7 years and would be way over these limited numbers.
What has your experience been with allergy shots?

Allergy shots

I don't keep up with the non-pulmonary allergy literature as I should. I often see atopic patients with or without true asthma who have allergy testing and then are started on allergy shots for desensitization. I have just seen someone who has been getting those three times a week for the past 6 years.
How often do you use allergy testing or shots in your practice? Any good literature on that in pulmonary practice?