I also thoroughly enjoyed The Art of the Tactical Carbine
In most of the training I’ve taken with tactical carbine and pistol operation, the emphasis has generally focused on winning the fight without much consideration for long term logistics. This has given much credence to the practice of emergency reloads – dropping the mag to get the fastest possible reload and more rounds on target. This has merit as civilians when we can just go out and buy new kit we’ve lost or soldiers and security contractors who can just go to a quarter master to replenish lost stores.
In an “End of the world as we know it” scenario, AR-15/M16 and Model 1911 magazines likely will be worth their weight in gold as there probably will be few if any retail shops or bin rats available to resupply anyone. If you watch the extra footage drill Chris Costa and Travis Haley perform, you’ll count no less than three mags dropped in under 60 seconds. There’s no guarantee you’ll be able to win a fight and be able to collect your kit and even if you do, dropping mags does add fatigue that can eventually cause them to break or malfunction.
To that end, it’s important to consider that while dropping your empty magazines (or any kit for that matter) may allow you to perform a reload a few seconds faster right now, it may also turn your semi-automatic carbine or pistol into a single shot, breech loader six months in the future.
While there’s strengths and weaknesses to both the emergency/speed reload and tactical reload/reload with retention, it’s a good habit to get into not taking for granted the ability to replenish your kit and training yourself to recognize what circumstances would merit either techniques.