It says in the Shulchan Aruch Harav in sif 5 and 6 that there are two opinions as to what garments are obligated in tzitzis:
- Since the blessing says "Lehisateif BaTzitzis", only garments which can be worn "KeAtifas Haishmeilim" are obligated in Tzitzis. Therefore, our Tzitzises which are too small are not obligated in Tzitzis.
- All garments which have four corners are obligated, as the formula of the bracha is not mentioned anywhere in the Torah. Therefore, our Tzitzises must have Tzitzis, but the blessing is "Al Mitzvas Tzitzis".
He says that the Halacha is like the second opinion.
In Sif 7, however, he says that if one wants to fulfill his obligation of wearing Tzitzis according to all opinions (and to be able to say "Lehisatef"), he should wear the tzitzis over his head with it draping down his back (which is ituf).
I have two questions on this:
- Is a Tallis Katan big enough to do Ituf? If yes, one should be obligated to place tzitzis on it according to all opinions. If not, what is the idea of draping it down his back?
- He says that one should do this if "he wants to fulfill his obligation according to all opinions, if he wants to say the blessing 'Lehisatef batzitzis'" ... If one wants to be stringent like the first opinion, he must do ittuf whatever blessing he says.