EPTIf a sunk and spore are only a building square away(meaning if you can place a hydraden/evo chamber between them) you can actually have a d-web overlap between them and disable both of them even though they are barely covering on the edge of both of them. So think about the actual surface area you're eliminating with and making zerg only be able to attack in limited confined areas which is what you want.
I think protoss progamers should really utilize corsairs a lot better and invest in fleet beacon and d-web research instead of trying the macro and ram units up against the hatchery walls tactic. In a pinch d-webs can still help in mobile fights as long as you place them well especially against walls and other terrain and those few seconds for them to move hydras and units out of the d-web area is still valuable time that their DPS is reduced effectively. Corsair purposes fulfill
1. Scouting
2. Killing OL, slowing down unit production and making them waste larvae
3. Denying map control which can open up possibilities for DT harass and can dictate the pace of the game forcing zerg to watch out for DTs, buying you time.
4. Discourages muta switch and avoids the situation of having your HTs sniped.
5. D-web to lay siege against a sunk/spore lurker defense and more easily take out expos while keeping your army alive. Protoss units by their nature are more expensive so to compensate they need to utilize all their abilities to win. So why not add d-web to help conserve your resources by allowing your units to fight longer, survive and snowball army advantage instead of trying to outmacro zerg and win by attrition unless you also successfully harass often times zerg can get by with a lot less and still defend with lurkers. Think about the game Larvae vs Rain few ASL seasons back. Rain was up more than 100 supply I think. How much resources Rain wasted with his army trying to ram his units against a few well placed lurkers hatchery/evo/den wall with sunk and spore. A few d-webs would disable a lot of those lurker/sunks and then he would just have his goons taking them down while zealots screen against the lings. I mean he had 100 supply adv for a lot of the game! Rain even did try storm drops multiple times while atking simultaneously but Larvae was just on top of his game and didn't lose as much as Rain invested into those harassments and eventually lost the war of attrition DESPITE BEING 100 SUPPLY ahead, can I emphasize that enough? Sure Rain's attacks could use some improvement and his decision making, but the fact that zerg can hold on with a lot less holds true which is why we know in PvZ protoss generally should be at least 15-20 supply ahead or he is LOSING since zerg units don't take up much supply they have a bigger army than what the population count suggests.
