The probies gotta do what they're taught to do!
All areas are different, and part of the fun(?) of discussing tactics are how everyone does it differently, or slight variations.
2-1/2 gallon cans are great -- in NYC. But we also have to remember no one else in the U.S. and few places in the world run at the staffing levels and density of companies as FDNY. 4-5 man engines and 6 man trucks and what, about 1 square mile per station on average? Was reading a National Geographic article last night that just casually mentioned a that there was two fire stations within the 1/2 square mile neighborhood. If your on a six man truck company, with plenty of 5 man engines and more 6 man trucks coming to your sign in the next few minutes, and you gotta get to a fire on the sixth floor of a big apartment building taking a can to help make a quick punch to be able to gain control of a door isn't a bad option. Now cans certainly have a place in other communities, but you gotta realize why your taking it with you and how it fits your department and buildings -- hopefully you're not taking it since FDNY does and a bunch of instructors at FDIC were copying them.
If your in a situation with two 3 man companies are gonna be working the two-story single family residence alone for awhile, taking a line with the "search" team is a different proposition. The attack team is hopefully headed for the fire, and the "search" team may very well be taking a line to the floor above and want to be able to deal with what they find, like flames extending in a balloon frame -- endangering not only them but the attack crew below.
There's very few "tactics" that are wrong. Most of the time when things go bad we're either not doing a set of tactics together like they should be done, or we're mixing and matching things (like using PPV while also having guys go through windows doing VES). The best classes I've taken have been taught by FDNY officers, but what I learn there isn't neccessarily something that will work back in my home district -- we don't have the constistency in the quality or numbers of staff as FDNY, and many other factors (like response times, building design, water supply, or even the life hazard to name a few). Doesn't mean we're a worse department than FDNY, just we have conditions that mean we have to do things differently. What's effective in your area is a better measure of how good your department is than whose tactics you use.
We can all learn from each other, and try out new things in a reasoned way and see what works better in our areas.
We can all go out a play. Play is a good thing. Play doesn't mean winging things and flying by the seat of our pants -- sit down and think out what you're gonna do, what's the safety issues, and let the troops now you're going out to experiment and try X, Y, and Z today and see what happens. If some of the stuff you play with works out, then you can make a formal training session on it, and then you can have drills to build profeciency on it. If some of the stuff just doesn't seem to fit, hey, you were just playing with the idea so abandon it.
A lot of times in the fire service we adopt mantras that Instructors like to say, and people never really question them. Instead of saying you need a minimum of 95gpm or 125gpm or 150gpm or whatever to make an initial attack, we got lazy and said you need an 1.75" line minimum. Now a long 1.75" line that's being underpumped delivers a lot less water than a 1" line pumped hard...but somehow we have tried to simply rates of delivery and hydraulics down to, "always pull at least an 1.75" and unfortunately the background of "so you can deliver at least xx gpm at xx psi" is lost.
In the end, it's up to use to explain to our probies how and why we do things the way we do in our own areas.