Personaly, I don't use deca that often anymore and when I do it's in low dosages just to keep the joints lubricated. It's a wonderful compound. And the dosage I suggested was pretty low.
I've seen a lot of crazy suggestions of gear over the years. Guys taking a gram and a half of test. 900mg of deca and throwing in winstrol, eq etc into the mix doing the shotgun approach. That's why I gave three very simple. very low dose cycles to get guys experience.
Personaly, I recommend test only cycles for first cycles too, but I don't think 300mg of deca is anything that's going to cause any problems. And as a strongman and former PL. I LOVE DBOL! If I could eat 50mg ed and not have my liver fall out I would do so year round.. lol. I think it stacks great with anything because it adds strength and size both so well when combined with a strong androgenic anabolic.
Also to note, I think Test should be the foundation of EVERY cycle. Not just something to stack with something else. Whatever else you take IMO is stacked with test. Never the other way around.
I'd never advocate 600mg of deca with 250mg of test.. I would however recommend the other way around.
I'm no bodybuilder but have friends who are.. I lean toward size and power over asthetics and symetrics
But the basic principles for AAS use remain the same. Just depending on what your goals are determines what AAS you may use.. although Test, Tren and dbol is good for everybody who trains no matter what your competitive sport... but that's just getting us farther away from the original topic.