Further evaluation

Question
I have son who recently turned 13 and has swam competitively year round for 4 years now.  We started slowly(2-3 days/wk) and he has progressed very well every year and has been swimming about 5 days/week for the last year.  Our swim club has several promising age groupers and the coaches train all kids in their group the same.  We do not expect special treatment from the group, and have always tried to have realistic expectations for our son.  Is there a time or stage where you would recommend a more specialized coach be introduced to evaluate or train our son? He has continually improved to the point where he has achieved T16 times in breast stroke and quad/triple A in the other strokes by age 12.  We realize early success is not always an indicator or future success, but also don't want to miss out on a window of opportunity if we should be seeking this.  He has never had any underwater evaluation and gets limited individual attention with his stroke technique. Thanks for your input

Answer
At 13 your son is still a little young to get involved with a "specialized" coach.  He still has a lot of growing to do and that will effect a lot in terms of technique.  My best advice is to stay where he is now and for you to talk to his coach about taking a look at his technique and making any adjustments necessary.
If you are interested there are many swim camps held during the summer that offer more intense stroke technique and possibly underwater evaluation.
Hope this helps
George