Couzens recommends no more than 5 CTL points per week for elite riders.
Adding 9 TSS per week to a rider with a CTL of 150-200 is trivial (5-6%) whereas it would cripple a 40 CTL rider, eventually.
WRT to the time constants, I had found that they did not represent my decay in my late 50's and I monkeyed around with them until they matched my HRV, mood, and general feeling of fatigue. I sent a note to Andrew Coggan and he graciously responded and if my memory serves, he said older fit riders can have different constants from the typical ones used by TP.
What I found worked for me was a constant of 10 IIRC with a 10 day Micro cycle and every 20 days (2 cycles), I would do 5 days easy as rest and then another 2 cycles of 10 days each. Very odd but it worked. I would be careful ramping too quickly