Sylk DOES NOT improve fertility or chanced of conception whatsoever. Anyone who needs a lube wtihout cutting odds of conception a small amount of Preseed or any sperm safe, conception friendly jelly like Conceive Plus or Yes Babi. The other site cares not about people's chances of conception so take what they say with a grain of salt.
I prefer people do e4d plus one at pos OPK rather than BD thru fertile window. BD thru may mean that your husband is depleted before your fertile window even truly opens so he's shooting little but dust by the time the egg shows up. Additionally it may even sway blue, so it's the worst of both worlds, you may end up swaying blue for something that doesn't help you get pregnant sooner. Every 4 days plus one is I believe the best balance between good odds of conception and
If you're ready to get pregnant, then go to SMEP. Don't try to "reinvent the wheel" here, there IS NO magic way to DTD that both ups odds of conception and still sways strongly pink. It's either one or the other. E4d + 1 is the best compormise. SMEP is the best way to get pregnant. Don't bother with any other combo because you expend all this mental energy trying to make some perfect unachievable scenario happen.