With the new LRM rules for direct fire, the aim was to make a support mech that can join the pack and shut down the enemy ECM using PPC fire then get a quick target lock with TAG. It works, the mech in manuevable enough to get in position, but its much harder to get locks overall with the new rules
reduces lock time i think. So no ECM + TAG locks faster in direct LOS, than ECM + TAG at least thats how i read it. Maybe your right with a BAP too ... Interestingly it looks like missile health will get a small buff next patch, as at the moment with ECM, AMS and longer lock times, its really hard to use LRMs.
TAG doesn't do anything but break ECM if you have LOS. It also allows other friendlies to get locks as if they have LOS. As of right now, there is no way to reduce lock time if you already have LOS.
You have to use Tag against ECM mechs, otherwise getting a lock takes too much time. Since ECM is not exactly rare, any build that makes LRM or SSRM its main weapon must include a tag. I did not try shutting their ECM down with PPCs - an interesting idea.
Well, ECM only increases lock time if you don't have LoS. If you can visually see the target, ECM simply reduces sensor range. Bringing TAG is therefore not supernecessary unless you plan to have a lot of shootouts beyond the final sensor range. The nice thing is mostly that your teammates can fire at the same target as you, so you can coordinate focus firing missiles to get through ECM. I think my equipment guide is a little out of date by now, I'll modify it a bit when I have time, as I did when the Artemis changes hit.