Same-Finger Bigram Drill (ed de ol lo)

The repositioning time itself can't be trained away — it's a fixed cost of the finger's own geometry, and every typist pays some version of it on these ten pairs. What varies between typists is a second, optional cost: a full stop while attention double-checks that the finger has actually arrived, stacked on top of the mechanical travel. That pause is a habit, not a requirement, and it's what this drill is aimed at removing.

Because no overlap is available, the temptation under speed is to start the second press a fraction early anyway, as though the pair could roll. On a shared finger that produces one of two failures: a dropped letter, where the second press lands before the first has released, or a doubled one, where the key repeats because the finger never really left — two of the specific error types Why You Make Typos (and How to Actually Reduce Them) covers in broader terms. Practising these ten pairs on their own, away from the rest of a sentence pulling attention forward, gives you room to notice which failure is actually yours.

The payoff shows up less in these exact ten pairs and more in the pattern itself: the moment you can feel a same-finger repeat coming, from a word half-read, is the moment you can commit to two clean, deliberate presses instead of one blurred attempt at a roll that a single finger was never going to pull off.

A roll works because two separate fingers share the load: the second one can begin its downstroke while the first is still lifting, so the total time is less than two full presses end to end. A single finger doesn't get that option — it's the same physical part of the hand for both letters, so the second press can't begin until the first has genuinely finished. That's the whole mechanical story behind why "ol" takes longer than a pair typed by two fingers of similar reach, like the ones in the Adjacent-Finger Roll Drill. Nothing about O or L individually is hard; the problem is that they're asking the same finger to do two consecutive, non-overlapping jobs.

"ed", "de", "ol", "lo", and "gr" only need their finger to move one row, so the mechanical cost is small even though the overlap problem is identical to the others. "un", "ny", "my", "ce", and "ec" raise the same shared-finger question but add a second row to the trip, which is why they tend to feel noticeably heavier in this drill even though the underlying issue — one finger, two presses, zero overlap — is exactly the same. The row-jump problem on its own, without a shared finger complicating it, is covered separately in the Row-Jump Bigram Drill; running both drills back to back separates how much of the slowdown here comes from the shared finger and how much comes from the extra distance.

If every attempt at these ten pairs comes out at roughly the same pace regardless of how deliberately you type them, the delay you're feeling is mostly the structural one, and there isn't much more to squeeze out of it. If slowing down and consciously committing to two decisive presses closes the gap compared with your fastest, most hesitant attempts, the time you were losing was the optional pause, not the finger's own travel — and that's the part that keeps improving with repetition, the way the Speed Building: Common Letter Pairs lesson introduces for bigrams generally before this drill narrows in on the one class where overlap is physically impossible.