Mine also wear clothes 99 % of the time and enjoy wearing them.
As to their coats, I am growing out both Jaden and Jewelina's coats. Jaden had a puppy cut this past summer but Jewelina's coat has never been trimmed. They get groomed twice daily, in the mornings and the evenings. I use a Mason Pearson brush and just recently got a CC buttercomb
I have never had any problems whatsoever with matting or knots, of course the both have silky coats so this does make a difference, but, I haven't noticed their clothes not making their hair as long are retarding their hairs growth rate. Both of their coats grow like weeds and like I said they were clothes all the time so I don't think it should cause a problem for you and your baby
