Correct use off gelpad

[Sandman@voeding.tno.nl]

I'm using a Celite gelpad. It has, according to the enclosed manual, a
sweat absorbing side so it could be used directly on the horse-back.
Other riders however draw my attention,  to use a (cotton) pad between
the horse-back and the gelpad on longer rides.
Has anybody any experience using a gelpad on both ways and its
(dis)advantages?

Gr
Hugo (and Lincoln)