"Jim R" nope, wrote in message
I'm not familiar with SRD, but I've used the Sikkens DEK base/topcoat
system
on my cedar porch. It looks great but I've also experienced some flaking
after the winter snows melt. Couple thoughts: moisture is the culprit
here,
Sikkens recommends coating the undersides of the deck boards, too - this
wasn't a practical option for me so there is some moisture that's able to
enter from underneath. Also, every little break in the finish - screw
holes,
scrapes from furniture, splits as the wood ages, etc. are water entryways
and will probably cause peeling.

I've had the same problem with a Cabot stain. It is in great shape on all
the vertical portion, but the decking went to hell after one season and it
is coated on the bottom also. The original PT wood is not all that smooth.
I figure water is getting in their and a couple of freeze/thaw cycles are
causing it to flake off. One a tiny gap starts, the rest follows quickly.
Ed