Now I know: it lasted just a couple of weeks. After giving the matter more thought, I decided to re-evaluate several razors. I'm glad I did. Not only did I give the Dorco Prime TTO another go, but this morning I shaved with my Lord LP1822L, and got a positively terrific shave! I had long ago dismissed the Lord LP1822L, with its L.6 razor head as being similar in design to my Merkur 33C Classic, but with the L.6 having a larger blade-bar span, which increased its tendency to nip if one wasn't too careful.
Well, since opening my mind to razors of slightly more aggressive shave character than my 33C, I've lightened my touch and opened my eyes to see several of my razors in a different light. Yep, some require more care while shaving, but the variety is not only kind of fun and has re-kindled my enjoyment of the process, but there are also the practical aspects.
For example, after back-to-back daily shaves with my c.1948 Gillette Tech and my Dorco Prime TTO -- both having a slightly positive blade exposure -- my skin needed a slight rest. But instead of retreating to the familiar safety of my Merkur 33, I chose the Lord LP1822L and made a mental note to use the same care that I would have with the Tech or the Dorco.
Bam! Top-drawer shave! I'm reminded that the Lord LP1822L may be another candidate for the best value in double-edge razors.
So another reason to keep razors on hand that offer a variety of shave aggression is to occasionally dip one's toe into the waters where more-aggressive razors be (aahhrrrr -- think pirate speak, matey).
Developing the flexibility to shave with razors of varying shave character can tweak one's skills to more often draw the best performance from one's shaving gear.