TJF97 - It is possible to train at 2 different FTO's
They need to synchronise your training and you will need to ensure that you co-ordinate things in a way that suits you and them.
1 - Take copies of training notes from each flight so that you/they are aware of progress.
2 - You will need to be very clear about what you have done and what is left to do (suggest you obtain a copy of the JAR PPL Syllabus from Pooley's)
3 - Be up front and ensure that everybody understands what is happening, why and when. Keep communicating effectively with both places and both instructors (do not play one off against the other "well Joe said I can land the aircraft and I only mess up landings when I am with you".
On a personal note you may find that your instructors may loose interest in managing your overall training (human nature and difference in style and personal preferences for how things are done) - so better to stick with one if you can. Good standardisation notes can help (Pooley's have these).