FWIW I Agree
The L fund is doing well enough. I see you selected the 2010 L Fund. I am 55 and I selected the 2020 L Fund based on the hope that I would not be withdrawing money until 2020 despite retiring earlier. I do not see a lot of advice on the official TSP site about which L fund to select so I think this is an interesting question. Should the L Fund choice be made on the anticipated retirement date, the anticipated withdrawal date (if later that retirement date) or on an overall assett allocation based on one's total assets including home, IRAs, CDs, investments and cash?
But the various L funds are doing fine and I wish you well with your choices.