Peel-Away 7
This may not help much, but I did a complete bottom job on my new-to-me 81 Oday 28 this past off-season (stripped to gel and then Interprotect 2000 and VC17).I found a good deal on ebay for their number 7 product. (Per a phone call with the company, there's no real difference between 7 and marine but I never tried marine so I can't say for sure). Anyway, there was a very thick coat of soft ablative that it removed pretty well, but it took two applications in most spots, maybe because I applied it too thin. It didn't seem to penetrate whatever was under the ablative (barrier? primer?) but that was pretty thin and not too hard to sand. It saved me a LOT of hours on the sander, but the cost was around 500 (two 5-gallon pails). You might wanna try a couple different types as deck paint is sure to be harder than what I dealt with.By the way, get a sander with a dust hose attachment and use a shop vac with a big pail of water in between. You and your neighbors will appreciate it. but then again you've got a pail of 'soup' to deal with.