actually, the "throw a party" makes a lot of sense. if you do a one-on-one with a person, it normally takes at least 5-15 minutes and sometimes can go even longer. assuming you can keep each one-on-one down to 5 minutes a piece, you're talking about 500 minutes (not including overhead of time in between actually doing the one-on-ones, which could be even more than 5 minutes itself) or just over 8 hours -- a full work day.
now, think about throwing a party for 100 people. you have them all in the same place at the same time (no switching from one person to the next overhead as in the 