Why firewarriors are such utter fail

Two initial things. These are facts, and only a handful of warseers, dakkaits, and BALSers dare disagree.

Cost: a squad of twelve is almost as much as two suits with plasma and missiles. It's 120 points for the warriors, versus 124 for the crisis team.

One-dimensional: Firewarriors only ever shoot. They don't move, run, redeploy, flank, contest, do combat, or disrupt. Their shooting is ineffective against everything except light infantry, and even a 4+ save of some kind makes the squad impotent.

Yet, forumgoers still say new players should build their armies around 'fire teams.' This angers me.
As any troll will tell you, stupid people don't answer to smart comments, so it's necessary to sink to their level before you can defeat them.

In other words, time for mathhammer.
Twelve firewarriors equal 12 shots. Obvious, yes? This is 120 points, too. Also obvious.
Since all their stats are horrible, it made perfect sense to give them a mighty ballisticskill of 3. This means 6 of those 12 shots hit. Very, very obvious - as mathhammer always is.
Now, say we're shooting at marines, you'll wound with 2/3's of those 6, so 4.
Marines have power armor, which - according to mathhammer - blocks 2/3's of all damage done.
In conclusion, your 12 firewarriors pump out enough dakka to drop ONE! marine.

Yeah, that's some great value you're getting out of those 120 points. I'm so happy 'veterans' are telling people they need a 'core' of firewarriors to 'carry the bulk of the heavy lifting.'

When something's so bad not even mathhammer can make it look good, you know you're dealing with the very worst of all 'specialist units.'
Now that all the little warseers are enraged, it's time for the meat.

Firewarriors are useless. Utterly useless.
Each team you take is a minimum of 60 points. Add 4 more, and you can buy an additional plasma/missile crisis. 10 more, you can splash on a grand total of ten extra kroot. 60 points is almost enough to pay for an unblinged broadside, or half of an ionhead.
The mathhammer above doesn't even begin to describe their uselessness. You see, most people stuff them in transports, so the 120 point squads rarely get to fire more than once a game, and are never cheaper than 200 points.

Yes, you need troops - after all, we're playing 5th edition, right? Yes, we indeed are, but - and this is where it gets tricky for seals on forums - 5th edition isn't about massed troops. It's about taking and holding things. You need to hold one, and contest all others.
Only troops can hold, but everything else can contest.

This means you don't need to take a billion points worth of firewarriors and devilfish.
It's enough if you have the mandatory 6 dudes stuck at homebase, camping your one objective, while the rest of your army moves out and contests the remaining objectives, or shoots the enemy to pieces.

"But where will the dakka come from if I don't have firewarriors? You gotta have firewarriors and warfishes! How can you win if you don't have firepower!?" Alright, I'll bite.

Here's my 'base' army.

Junior commander: fireknife setup - 87
2 bodyguards: fireknife setups, 2 targeting arrays, blacksun - 167

Junior commander: fireknife setup - 87
2 bodyguards: fireknife setups, 2 targeting arrays, blacksun - 167

2 crisis suits: fireknife setups, teamleader - 129

2 crisis suits: fireknife setups, teamleader - 129

2 crisis suits: fireknife setups, teamleader - 129

6 firewarriors - 60
10 kroot - 70
10 kroot - 70

6 pathfinders: devilfish; smart missile system, vehicle multi-tracker, disruption pod, targeting array - 192

Hammerhead: railgun, burstcannons, vehicle target lock, vehicle multi-tracker, disruption pod - 170
Hammerhead: railgun, burstcannons, vehicle target lock, vehicle multi-tracker, disruption pod - 170
Hammerhead: railgun, burstcannons, vehicle target lock, vehicle multi-tracker, disruption pod - 170

This is a '2000 points' list, which isn't really at 2k. Sometimes, I switch in drones, blacksuns (not to be confused with purple suns) for purposes other than wound-allocation, or 'specialist units' (vespid, shapers, carbine warriors) for the hell of it, or cut out things to fit into lower points limits. It's far from 'the best,' and nowhere near optimal.
Years ago, I ripped the mixed guns of my suit armada, and organized them as above. This came about because I was convinced the forums were all wrong, and there was more to the codex than their tactica threads and so called 'experts' told me.
Since then, I've not lost a single objective-focused game. How does that work? I only have three troops, and tons of small, fragile squads, after all.

Easy.
When the opponent's units are all either dead or dying, he can't contest or capture anything.
Tau are damage dealers - not tanks or campers. Play to your book's strengths, and ignore the forumitis that surrounds this codex.

A standard 'fish of fury' team consists of twelve warriors aboard a devilfish. With all the common upgrades for the transport, this is 235 points minimum.
235 points for 12 guys that die when they dismount, ridin' dirty in a transport that doesn't want to get close to the enemy, yet has range 24 guns at best.

To nail the point home, my 'command squads' are 254 points each. Why are you taking the fish of fury again?