in 6v6 or whatever you're playing.
Let's create a fictional situation in 6v6. Map is Tanith and aliens got waste. You know the aliens would love to baserush sooner or later. Aliens drop west acc and Fusion nodes.
I send 2 to dbl and the rest 3 build the ip, armory. I see that the hive is waste, so I drop a pack of mines and an obs. Cappers die at dbl quite bad, but the sg push through chem moves quickly and faces little resistance. At this point you can assume that either they're going to ambush somewhere closer to fus or its a baserush. Meanwhile I've got one guy capping sat side, 3 at sg push at cargo and one guy basically baseguarding and keeping the waste side clear. Since my obs is placed on the waste facing wall of ms, I can see the baserush coming early, 4 dots outside ms. I've got the 'baseguard' at base, and I drop him a sg, assuming its about 3 skulks and a lerk by a quick judge. Meanwhile the sg team moves to fus and starts shooting the rt with all they've got. What happens, is they get the baseguard down due to the bad reg, nice dodging, bad aim, bad medding, whatever and move to obs with 4 guys. I beacon the same moment I can see that fus rt is going down. The obs starts to beacon, but gets chewed down milliseconds before finishing, since 4 biters pretty much instakill it. I get the obs at fus, but it takes time before I can afford the beacon and I practically lose the round there.
My biggests regrets: Possibly not hopping out. Its a bit of a gamble always, this time it might have worked better, since my medding failed anyway. Then again, the fus ms offers nice cover after you can clear the middle. I doubt I'd have killed the lerk on my own even if I got the 3 skulks with my baseguard. The unstable reg of some european servers doesn't help the decision either.
Not dropping another pack of mines for the obs when I saw the rush coming. Obiviously you haven't got much time, but even a single mine at obs might have helped. Maybe planting the first pack at obs instead of the ip. Ip is better off against 2 skulks, since one has to take out the comm while the other gets blown by the mines while trying to kill the respawning baseguard. Also the baseguard could probably have used the ip mines to blow up some skulks.
Maybe pushing through central acc with sg, or pushing west access rt. I'd have loved to push fus since I had the pg teching after a few scans, but that leaves your base quite open on waste side, no matter which route you use.
Not having 2 guys at waste side of the map. I needed one guy to cap sat side, but maybe pushing with 2 marines only, dropping one guy to cap. Then again, you pretty much need those 3 marines to fight off the res defenders if there are any. Too bad I saw that there was so little defence when it was too late already.
Not beaconing earlier. The rt had gone down anyway if I had becaconed a second earlier. I needed the rt down for sure though, since I was lacking the upgrades and needed times before the fades started messing up.
Not capping double with three. Gamble once again. This time I lost with my two marines. More res and I could have reloced to fus for example. Never crossed my mind while playing though. Probably couldn't have afforded it anyway, at least not after losing 15 to the beacon that never finished.
Anything else you want to point out. I sure learn about every baserush, but I feel a bit uncomfortable learning through mistakes while there are 5 others losing too.
E: Meh, epic typoes even at the topic.