sumo, who is this "PR" you are talking to? By "PR" do you mean "Park Ranger"?  
The Whitney Zone isn't in any "park", so PR is confusing. It is in the Inyo National Forest. While the peak is in Sequoia National Park, I doubt anyone from that park is paying any attention to trails outside their park.

Whoever it is, I wish they would stop telling people this. It is now way past the time, compared to other years, when people have switched over to using the switchbacks. If you have an ice axe and crampons, there is NO place on the switchbacks that cannot be easily navigated. If you DON't have traction equipment, then using the chute is highly dangerous when it is icy (mornings and later afternoons through the night).