I have no idea how much miles you're allowed to travel but I've been told once by a WP agent about a maximum number of segments (she didn't tell me the allowed #, just that my itin. would require too many segments [no mention of max miles]). In my opinion, if you plan an itinerary of 3 segments each way, you shouldn't have to worry
One thing I wonder though, can WP agents bypass these mileage/segment limits if awards aren't available on all direct flights or flights with one or two connections? Does status (SE, G, PE) influence their decision?