It will work. How well depends on your operating needs, length of feedline,
whether you are planning to use it on bands that don't have traps, what
radiation pattern you want, etc.
If you are just doing this to reduce feedline losses, it might or might not
actually do that. You can use VK1OD's transmission line loss calculator:http://vk1od.net/calc/tl/tllc.php
to compare the relative losses with Mismatch: ZLoad = 50 ohms.
For example, I compared 100' of RG-213 with Wireman 551 feeding a
50 ohm resistance on 20m and the ladder line was very slightly higher
loss. That would probably argue that, given the need for a tuner to
match the ladder line, the coax feed probably would be a better choice,
at least on the bands where the dipole is resonant.