This is simply not true. See my post on the matter (http://www.reddit.com/r/thebutton/comments/318501/clicking_doesnt_reset_to_60seconds_theory/cpz83uv)

You can watch the data streaming to your browser from the reddit servers. It's particularly easy to see that this is not the case when the timer got all the way down to 42. There is never a partial reset or increment. There are only decrements or a full resets. This is true for the many hours of logs I have.

presses  security hash                           timer  time
--------------------------------------------------------------
488,850 0abd07dcd0fc930f62a00bc5b44ed5f26f73a883    55  2015-04-02-17-37-20
488,850 dd48e6d313adf5747111e726ebb282a5e70db93b    54  2015-04-02-17-37-21
488,850 94d008740d3fe162bcc7bc842ba4ce2315670e83    53  2015-04-02-17-37-22
488,850 18bc8a11e36b4964516ca7ca81b2240850adb80a    52  2015-04-02-17-37-23
488,850 a1ffbadce881cb1c723ba909b7cef35a8deef8ca    51  2015-04-02-17-37-24
488,851 46155ed57b278514bfe8f21c590b7a94487e3c86    60  2015-04-02-17-37-25
488,851 aa8ca300f865bc5df995beb971b300e9cacbbb9a    59  2015-04-02-17-37-26
488,851 e8d8eb28f8e055d66b5a97fa0d978c51b3193749    58  2015-04-02-17-37-27
488,851 cf3abe9321ce07fe2f0bcb4d885fd7ca9cce5ee4    57  2015-04-02-17-37-28
488,851 659956e85832263a947a3217a7006c62e0f7c6ad    56  2015-04-02-17-37-29
488,851 6974ae6137837fabb414fb704b79ec76529281da    55  2015-04-02-17-37-30
488,851 1c570ea85933dd1b3d7cc1118086fa54287c1872    54  2015-04-02-17-37-31
488,851 2e44557b6cfb1f0923d0ef184afb43fa6313ea0c    53  2015-04-02-17-37-32
488,851 fe7442a2f5e4c99ab641cd8af024b15e180109b5    52  2015-04-02-17-37-33
488,851 646fd006eb8e24cd37c07fde9fff08e670220ec5    51  2015-04-02-17-37-34
488,851 100e94a47ef4d3dbc0ae9457eb0a907a48e3e15e    50  2015-04-02-17-37-35
488,851 10dcef5931cd66aa7884f8f87d46f5ed2ac23526    49  2015-04-02-17-37-36
488,851 0ebf8767fa44091f5cd17793844c173f72c34e19    48  2015-04-02-17-37-37
488,851 4679a3917a3dd8c874a6faf4458842edf2e548ac    47  2015-04-02-17-37-38
488,851 a625beab0aa1c4745df3a1d47a2ad76f0a7b1413    46  2015-04-02-17-37-39
488,851 bf19527ac777303cc6e2412c351e16c4fc68a07a    45  2015-04-02-17-37-40
488,851 ef6a821149c2c628adeade3c552b787aa2a51bb2    43  2015-04-02-17-37-41
488,851 b5754b896069f4362a6feb4111ac1875fb70c139    42  2015-04-02-17-37-42
488,852 7260ee4806cbbea841d96778150d9eb241c5882e    59  2015-04-02-17-37-43

You can also see how the full resets in this portion of the log were caused by only 1 press, and not, say, 20 separate presses.