> "Setting the T1OSCEN and TMR1CS bits to '1' will enable
> the LP oscillator to clock TMR1 while the microcontroller is
> clocked from either the INTOSC or LP oscillator. Note that
> the T1OSC and LP oscillators share the same circuitry.
> Therefore, when LP oscillator is selected and T1OSC is
> enabled, both the microcontroller and the Timer1 module share
> the same clock source."
> 
> The first statement there says that I can do this -- ie: separate
> INTOSC for the microcontroller and the LP oscillator (with
> 32.768khz external crystal) to clock TMR1.
> 
> But the next 2 statements say that they are the same oscillator,
> and hence both the microcontroller and Timer1 module will have
> the same clock source.

To my eye it says Timer1 and LP share the same circuitry, and
INTOSC is entirely separate

> "Setting the T1OSCEN and TMR1CS bits to '1' will enable
> the LP oscillator to clock TMR1

Therefore if you have a 32k crystal on T1OSC pins (which are
also the primary OSC pins), TMR1 will be clocked by the 32k
crystal. You may also choose to run the core on that 32k (if LP
is selected as the core clock source) or use INTOSC for the core,
whilst TMR1 will use 32k

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