As a Lubavitcher I and a plethora of *serious* Chabad rabbis am/are adamant about bochurim tucking in their shirts. My Rosh Yeshiva (and mashpia for that matter–that’s Chabad jargon for the Lubavitchers in the house) will often stop bochurim even as they walk into the zal and ask them why their shirt is untucked.
When my own hat started looking old and worn out (I simply did not have money for a new one), my hat somehow “disappeared”. I went berserk looking for it, but in the end I was left with no choice but to ask my parents to help me pay for a new one (over a year later I found the hat in the teachers’ lounge while helping a rav with something there…).
Yes, a Lubavitcher bochur needs to look appropriate *especially* when travelling around outside of yeshiva. The Rebbe’s chassidim need to present themselves with respect.
But the tie thing I think will fall into what some people are saying here about being too “megusham”–that is, making too big a deal over physical appearance.
That being said, I strongly hold that in the right circumstances, it would be absolute shtus (d’leumas zeh –more Chabad jargon…) not to wear even a tie if it were deemed appropriate to the bochur or chossid’s role thereof.
A shliach I know wears a tie, and even asks one of the chassidim in his kehilla to do so to make sure that the mekuravim there don’t feel out of place amongst the other chaassidim who don’t wear one.
One last example: JJ Hecht was a secretary of the Rebbe, and one whose role involved dealing with the most high-class officials; essentially he was like the Rebbe’s embassador/spokesperson. Well, the guy was poor like no other, yet he took enormous sums of money as loans in order to buy the most expensive top-hat (as was considered high class at the time–you can see it in the videos) and most high class suit. He reasoned (correctly) that as someone representing the Rebbe he has to look accordingly.
Now how is it that he allowed himself to wear such expensive clothes as a chassid? Isn’t it megusham??? So if you wear it with your own appearance in mind then that would be true. But he was clearly doing so for a higher purpose and therefore did not fall into risk…
Thus is it that I assert, that indeed Lubavitchers need to look as dignified as possible, within the appropriate boundaries, especially in the eyes of those to whom we are representing the Rebbe.
*Standing ovation*