Nope. I am an instructor, but most of my diving is for me. All of my recent inwater failures have been from crud in the water. I surfaced in the Cistine sink in the Peacock cave system and it was filled with duck weed. I even used a blast of air to clear it where I came up. For those not familiar with the system, climbing out at Cistine is almost impossible, and especially so for someone like me. As I started my trek back P1, some duck weed had become lodged in the exhale valve, allowing water to sneak back in during inhalation. I switched to my left tank (sidemounting) only to find an even wetter breathing reg. So, while I'm in transit and breathing gently off of my reg, I pulled off the face of my reg and cleared the debris. Once clear, I switched to that reg and did the same on the other and made a clean exit at P1. Having my regs only finger tight would allow me to switch first stages around as needed. IOW, if I couldn't clean out either first stage, I could have taken the reg off of my deco bottle and tried it, keeping my options open.