Before I cast my vote, I hope you understand I FULLY comprehend the use for these JT's and you reasoning for them.
With that being said, -1.
DU's job is to provide for a defensive front and being experts in such maneuverings. You mention of lancer is understandable but HS's intention is to be a fast based, non-defensive squad. This again, does not apply to the rest of DU. Your mention of subunits quite confused me on the intention of such but thats besides the point. I believe this suggestion has long term implications on the use of DU if passed for the future.
TL;DR - DU is a defensive battalion. JT wouldn't make sense in any capacity. It wouldn't be "unfair", it would just be redundant. imo.